Summarize the following court judgment. Civil Appeal No.877 of 1974. From the Judgment and Decree dated 17.11.1971 of the Allahabad High Court in First Appeal No. 171 of 1966. D.N. Mukherjee	 G.S. Chatterjee and A. Bhattacharjee for the Appellant. Prithvi Raj and Mrs. Shobha Dikshit for the Respondent. The Judgment of the Court was delivered by VENKATACHALIAH	 J. This appeal	 for enhancement of compensation	 by Special leave	 arises out of and is directed against the judgment and decree dated 17th November	 1971 of the High Court of Allahabad in First Appeal No. 171 of 1966 affirming the Award and Decree dated 13.12.1965 of the Ist Addl. District Judge	 Varanasi	 made in a Reference Under Section 18 of the Land Acquisition Act 1894. Property known as "Gopal Lal Villa" a sprawling 60 year old building of about 25	000 square feet of plinth area comprising of 35 rooms	 halls and other appurtenances	 its large 23.66 acre grounds with 431 fruit and 13 Timber trees; 12 Bamboo clumps	 situated on the outskirts of the City of Varanasi	 originally part of the estate of Raja P.N. Tagore	 and now vesting in the Administrator General	 West Bengal	 was acquired pursuant to the preliminary notification	 published in the Gazette	 dated	 4.7.1959 for the purposes of the education department of the Government of Uttar Pradesh. Before the Land Acquisition Officer	 Appellant claimed compensation of Rs.8	00	580 (at Rs.352 per decimal) for the land; Rs.3	50	000 for the building and structures; Rs.41	010 for the tree growth; and Rs.5	000 as compensation for change of residence. The Land Acquisition Officer	 however	 by his Award dated 4.11.1961 under Section 11 of the Act determined the market value of the land at Rs.3	31	340 valuing it Rs. 140 per decimal (or Rs.14	000 per 1032 acre); of the building and structures at Rs.57	660 and of the treegrowth at Rs.355.83. Appellant	 not having accepted the offer contained in the award	 sought for a reference under Section 18 of the Act to the Civil Court in proceedings pursuant to which the District Court enhanced the market value of the land to Rs.4	73	200 (from Rs.140 to Rs.200 per decimal) leaving the valuation of the building and the tree growth undisturbed. The High Court has affirmed the Award dismissing appellant 's claim for further enhancement before it. We have heard Shri D.N. Mukherjee	 learned counsel in support of the appeal and Shri Prithviraj	 learned Senior Advocate for the respondent. We have been taken through the judgment under appeal and the evidence on record. On the contentions urged at the hearing	 the following points fall for consideration: (a) Whether the estimate of the market value of the acquiredland at Rs.200 per decimal is unreasonably low and is arrived at ignoring the evidence on record and settled principles of valuation? (b) Whether the valuation of the buildings and structures at a mere Rs.57	660 calls for an upward revision? (c) Whether the award made for the tree growth is inadequate and is required to be valued higher? (d) Whether appellant is entitled to the benefit of Sec. 23(2) of the Act as introduced by the U.P. Law Acquisition (Amendment) Act 1972 providing for solatium and	 further	 to higher rates of solatium and interest under the Central Amending Act (Act No. 68 of 1984) on the ground that proceedings were pending in appeal before this court on the dates these amendments came into force? 4. Re: Contention (a) The acquired land had the potentiality for building purposes. Learned District Judge found that: ". The Land Acquisition Officer himself realised this fact and has observed that "the land under acquisition is 1033 situated within the Corporation limits in Mohalla Orderly Bazar	 a thickly populated locality and is near to Kutchery. It has	 therefore	 a potential value as building site. " I may add here that though the acquired land is at a distance of about 3 to 3 1/2 miles from the main markets of Varanasi City	 yet every thing of daily need and of day today utility is available in the market which exists in the locality of the acquired land. It may also be added that the land adjacent to the west of the acquired land known as 'Tagore Nagar ' formerly formed part of this Gopal Lal Villa and both were covered by one boundary. The land of Tagore Nagar has been divided into small portions and a colony with residential quarters has grown up there. This was already in existence before the present acquisition . ." The determination of market value of a piece land with potentialities for urban use is an intricate exercise which calls for collection and collation of diverse economic criteria. The market value of a piece of property	 for purposes of Section 23 of the Act	 is stated to be the price at which the property changes hands from a willing seller to a willing	 but not too anxious a buyer	 dealing at arms length. The determination of market value	 as one author put it	 is the prediction of an economic event. viz	 the price outcome of a hypothetical sale	 expressed in terms of probabilities. Prices fetched for similar lands with similar advantages and potentialities under bona fide transactions of sale at or about the time of the preliminary notification are the usual	 and indeed the best	 evidences of market value. Other methods of valuation are resorted to if the evidence of sale of similar lands is not available. In the District court	 appellant relied upon eight transactions of what	 according to him	 were sale	 of similar lands. The transactions at Ext. 18	 20	 21 and 22	 dated	 25.3.1952	 1.12.1955	 11.8.1953 & 11.7.1957 respectively were rejected by learned District Judge on the ground that they were long enterior in point of time to the acquisition and lacked the element of contemporaneity. 23 dated	 25.10.1958 and Ext. 24 dated	 18.8.1960 were also held not to afford reliable evidence of market value on the ground that while in the former case the property was sold along with a construction thereon without any indication as to the apportionment of the price between the land and the construction	 in the latter case the sale was about an year subsequent to the date of the preliminary notification. 1034 What remained were the evidence of sale transactions at Exts. 2 and 19 dated 16.9.1958 and 22.12.1958 respectively indicating a price of Rs.1250 and Rs.900 per biswa respectively. The District Judge struck an average of the two and fixed the rate at Rs.1075 per biswa which worked out to about Rs.350	 or thereabouts	 per decimal. But since Ext. 2 and Ext. 19 related to very small plots	 the learned District Judge on some calculations of his own	 fixed the rate of Rs.200 per decimal for the acquired land. Shri Mukharji in support of the appellant 's claim @ Rs.352 per decimal submitted that the High Court	 in affirming the valuation of the land at a mere Rs.200 per decimal	 overlooked certain settled principles of valuation in that it approved the process adopted by the learned District Judge of striking an average of the valuations reflected in Ext. 2 and Ext. 19	 while the higher of the two figures indicated by Ext. 2	 should have been adopted. Learned Counsel submitted that the acquired land	 though situate about 3 1/2 miles away from the heart of Varanasi City	 had all the potentiality for use for building purposes and that the rejection of the evidence of market value afforded by Ext. 24	 the transaction of sale dated 14.7.1960 which indicated a price of Rs.2	000 per biswa on the ground that it was an year later than the preliminary notification was erroneous. It is trite proposition that prices fetched for small plots can not form safe bases for valuation of large tracts of land as the two are not comparable properties. (See Collector of Lakhimpur vs B.C. Dutta	 AIR 1971 SC 2015; Mirza Nausherwan Khan & Anr. vs The Collector (Land Acquisition)	 Hyderabad	 [1975] 1 SCR; Padma Uppal etc. vs State of Punjab & Ors.	 [1971] 1 SCR; Smt. Kaushalya Devi Bogra & Ors. vs The Land Acquisition Officer Aurangabad & Anr.	 [1984] 2 SCR. The principle that evidence of market value of sales of small	 developed plots is not a safe guide in valuing large extents of land has to be understood in its proper perspective. The principle requires that prices fetched for small developed plots cannot directly be adopted in valuing large extents. However	 if it is shown that the large extent to be valued does admit of and is ripe for use for building purposes; that building lots that could be laid out on the land would be good selling propositions and that valuation on the basis of the method of a hypothetical lay out could with justification be adopted	 then in valuing such small	 laid out sites the valuation indicated by sale of comparable small sites in the area at or about the time of the notification would be relevant. In such a case	 necessary deductions for the extent of land required for the formation of roads and other civic 1035 amenities; expenses of development of the sites by laying out roads	 drains	 sewers	 water and electricity lines	 and the interest on the outlays for the period of deferment of the realisation of the price; the profits on the venture etc. are to be made. In Sahib Singh Kalha & Ors. vs Amritsar Improvement Trust and Ors.	 (See 	 this court indicated that deductions for land required for roads and other developmental expenses can	 together	 come up to as much as 53%. But the prices fetched for small plots cannot directly be applied in the case of large areas	 for the reason that the former reflects the 'retail ' price of land and the latter the 'wholesale ' price. The sale transaction at Ext. 24 was an year later. Such subsequent transactions which are not proximate in point of time to the acquisition can be taken into account for purposes of determining whether as on the date of acquisition there was an upward trend in the prices of land in the area. Further under certain circumstances where it is shown that the market was stable and there were no fluctuations in the prices between the date of the preliminary notification and the date of such subsequent transaction	 the transaction could also be relied upon to ascertain the market value. This court in State of U.P. vs Maj. Jitender Kumar	 (See observed: ". . It is true that the sale deed Ext. 21 upon which the High Court has relied is of a date three years later than the Notification under section 4 but no material was produced before the Court to suggest that there was any fluctuation in the market rate at Meerut from 1948 onwards till 1951 and if so to what extent. In the absence of any material showing any fluctuation in the market rate the High Court thought it fit to rely upon exhibit 21 under which the Housing Society itself had purchased land in the neighbourhood of the land dispute. On the whole we are not satisified that any error was committed by the High Court in relying upon the sale deed exhibit 21. ." But this principle could be appealed to only where there is evidence to the effect that there was no upward surge in the prices in the interregnum. The burden of establishing this would be squarely on the party relying on such subsequent transaction. In the present case appellant did not endeavour to show that between the date of preliminary notification i.e. 4.7.1959 and the date of Ext. 24 i.e. 18.8.1960 there was no appreciation in the value of land in the area. Therefore	 Ext. 24 cannot be relied upon as affording evidence of the market 1036 value as on 4.7.1959. We cannot accept the argument that the price indicated in Ext. 24 should be accepted after allowing an appropriate deduction for the possible appreciation of the land values during the period of one year. Apart from other difficulties in this exercise	 there is no evidence as to the rate and degree of appreciation in the values of land so that the figure could be jobbed backwards from 14.7.1960 to 4.7.1959. It appears to us that even if the value at Rs.1	250 as on 27.8.1958 indicated by Ext. 2 is adopted and something is added thereto for the possible appreciation for the period till the preliminary notification	 also taking into account the trend of appreciation in the prices in the area as indicated by Ext. 24 and the value of small developed sites is estimated somewhere between Rs.1	400 and Rs.1	600 per biswa or Rs.450 to Rs.500 per decimal	 yet	 the valuation made in the present case does not call for or justify any upward revision at all. There is a simple way of cross checking these results. The value of small plots Rs.500 per decimal as now estimated represents what may be called the "retail" price of the land. What is to be estimated therefrom is the "wholesale" price of land. In Bombay Improvement vs Mervanji Manekji Mistry	 (See AIR 1926 Bombay 420) Mecleod CJ suggested a simple rule: ". .Valuation cases must be dealt with just as much from the point of view of the hypothetical purchase as of the claimant. The valuation itself must often be more or less a matter of guesswork. But it is obviously wrong to fix upon a valuation which	 judged by everyday principles	 no purchaser would be likely to give . ." ". .I have always been adverse to elaborate hypothetical calculations which are no more likely to lead to a fair conclusion than far simpler methods. But	 in any event	 no harm can be done by testing a conclusion arrived at in one way by a conclusion arrived at in another . ." ". .A very simple method of valuing land wholesale from retail prices is to take anything between one and half onethird	 according to circumstances of the expected gross valuation	 as the wholesale price. ." (emphasis supplied) In the present case	 Rs.200 per decimal for the large extent of the 1037 acquired land works out to 40% of the "retail" price even if we take	 Rs.500 as the "retail" price. That apart	 in the case of land with potentialities for a more profitable use	 it is necessary to acknowledge	 and make due allowance for	 the possibility that the land might not be applied for the prospective use at all or not so applied within a reasonable time. There is	 therefore	 no justification to interfere with the determination of the market value of the land approved by the High Court. Contention (a) is accordingly answered against the appellant. Re: Contention (b) The District Court proceeded to value the property on the "Land and Building Method". The appositeness of this method to the present case was not debated before us. Usually	 land and building thereon constitute one unit. Land is one kind of property; land and building together constitute an altogether different kind of property. They must be valued as one unit. But where	 however	 the property comprises extensive land and the structures thereon do not indicate a realisation of the full developmental potential of the land	 it might not be impermissible to value the property estimating separately the market value of the land with reference to the date of the preliminarynotification and to add to it the value of the structures as at that time. In this method	 building value is estimated on the basis of the primecost or replacement cost less depreciation. The rate of depreciation is	 generally	 arrived at by dividing the cost of construction (Less the salvage value at the end of the period of utility) by the number of years of utility of the building. The factors that prolong the life and utility of the building	 such as good maintenance	 necessarily influence and bring down the rate of depreciation. Hari Shanker Misra PW 3 referring to the nature and quality of the building stated: ". The Northern part of this Villa was double storeyed and rest was single storeyed. Its plinth was 3 feet high and rooms were 14 feet high. The building bore 35 rooms and besides this there was a big hall 65 feet x 22 feet. Its floor was made up of some patent stones. Some monthly some market and Vkiya were stoned. The doors were 8 feet x 4 feet and they were made up of Burma teak wood and up ways were double doored. When Improvement Trust oc 1038 cupied the property of Nejai at that time building was well maintained. Over and above the main building there were manager quarters. Kitchen	 out house	 servant quarters	 Chowkidar quarters and a stable. Now they were in good condition. Its boundary wall was 7 feet and at some places they were 8 feet high. This also consists of 2 iron gates. One is main gate and the other one is by its side of some distance. " Learned District Judge based his valuation almost entirely upon the report of the Chief Engineer	 estimating the building at Rs.57	660. That report itself was not brought on record in the proceedings of reference. It is not clear from the judgment of the High Court whether this estimate of Rs.57	660 represented the cost of replacement of the structure less depreciation or whether it represented merely the salvage value of the building. High Court rejected the Valuation Report	 Ext. 1 relied upon by the appellant on the ground that it was made with reference to a date which was an year later than the preliminary notification. The High Court observed: ". The appellant had examined Narain Chand Das	 an Overseer who had assisted the Executive Engineer	 in preparing the valuation of the constructions and the well. The report of the Executive Engineer is Ext. 1 on the record. It appears from the said report that the valuation was determined on the basis of the rates prevailing in the year 1960 where as the preliminary notification in the instant case was issued in the year 1959. Moreover	 this building appears to be about 60 years old and the market value thereof could not be determined on the basis of the cost of constructions prevailing in the year 1960. This method of calculating the market value of the property is obviously erroneous and cannot be accepted. No other evidence was produced by the appellant to determine the value of the constructions and the well. The evidence produced by him being not satisfactory	 the compensation already determined by the Land Acquisition Officer in respect of this item of the property was not liable to be enhanced. ." We are afraid the estimate of the proper market value of the building has not received the requisite attention both before the High Court and the District Court. It is no doubt true that Ext. 1 was prepared on 20.7.1960	 an year after the date of the preliminary notifi 1039 cation in the present case; but the extent of the built area was about 2	500 sq. 1 gives a breakdown of the area of the various parts of the building and sets out the nature of the construction and proceeds to estimate the value in terms of the then current PWD rates less depreciation of 20%. The rates adopted were not particular to the date of valuation i.e. 20.7.1960. The PWD rates are operative over a period	 generally for an year or so. The extent or the quality of construction were also not in dispute. The main building of an area of 18828 sq. consisted of 35 rooms	 and a big hall with 'Marble Flooring '	 'Burma Teak Shutters '	 'Stone Slab Roofing '	 a portico with 'Glazed Gracian Pillars ' etc. In Ext. 1	 the main portion was valued at Rs.12 per sq. Apart from the main building	 there were other appurtenances such as the Managers ' quarters	 kitchen house	 chowkidars ' quarters	 out house	 stables	 pucca wells etc. The other structures have been valued area wise at much lesser rates	 according as the nature of the construction. The decendants of Raja P.N. Tagore	 it was claimed	 were residing in the building till a few days before possession was taken. There is no evidence to suggest that	 the rates mentioned and adopted in Ext. 1 were not rates valid for a spread out period. It appears to us somewhat unreasonable that the extensive building of 25	000 sq. with big halls and 35 rooms constructed with quality material	 marble flooring	 burma teak joinery should be valued at a mere Rs.57	660. No case was made out that the building had lost its utility and that only mode of valuation appropriate to the case was one of awarding merely the salvage value. The building	 according to the evidence	 was quite strong though about 60 years old at the time. Having regard to the circumstances of this case	 the appropriate thing to do would have been to set aside the award in so far as the valuation of the building is concerned and remit the matter for a fresh determination of its market value as on 14.7.1959. But the parties have been at litigation for decades. The acquisition is of the year 1959. We	 therefore	 thought and put to the learned counsel on both sides whether in the interests of justice	 it would not be proper to make some rough and ready estimate	 drawing such sustenance as the evidence on record could afford and impart a quietus to this vexed litigation. Learned counsel very fairly submitted that this would be the appropriate course. In the very nature of things	 the exercise that we make	 must share the imperfections of the evidence on record. But then	 some element of speculation is inevitable in all valuations. In the 1040 best of exercises some measure of conjecture and guess work is inherent in the very nature of the exercise. We may first proceed to estimate the prime cost of the building. The measurement set out in Ext. 1 is not disputed. If Ext. 1 is taken as the starting point for the estimate of cost of replacment as on 4.7.1959; the depreciation of 20% allowed in Ext. 1 has to be added back and	 further	 some deduction towards the possible escalation of costs of construction between the date of preliminary notification and of the period of validity of the rates adopted in Ext. 1 has to be made. On this basis	 the cost of replacement could be estimated at about Rs.4 lakhs. This works out to Rs.16 sq. on the average. Even in respect of 1959	 this figure may not be much	 having regard to the quality of the construction. From this sum of Rs.4 lakhs	 depreciation for the past life of 60 years of building would have to be deducted. Depreciation depends upon and is deduced from factors such as the cost of the construction; the expected life span; its salvage value realisable at the end of the period of utility etc. Rate of depreciation is generally	 the prime cost less salvage value divided by the life span. These	 of course	 are matters of evidence. In the present case	 if we make a rough and ready estimate of the salvage value at say	 10% of the cost and estimate the period of utility of life span of the building at	 say	 90 years	 the depreciation which is the annual loss of value due to physical wear and tear works out to about Rs.4	000 per year or roughly 1%. Without going to the finer details of the calculation of the depreciation on the progressive written down values	 we think	 an estimate of 50% of the cost of the building may	 again on a rough and ready basis	 be deducted towards depreciation. The market value of the building as on the date of the preliminary notification could accordingly be fixed at Rs.2	00	000. Accordingly	 the compensation for the buildings and structures is enhanced from Rs.57	660 to Rs.2	00	000	 point (b) is held and answered accordingly. Re: Contention (c): So far as the tree growth is concerned	 it is trite proposition that where land is valued with reference to its potentiality for building purposes and on the basis of prices fetched by small sites in a hypothetical lay out	 the tree growth on the land cannot be valued independently on the basis of its horticultural value or with reference to the value of the yield. But this principle does not 1041 come in the way of awarding the timber value or the salvage value of the tree growth after providing for the cost of cutting and removing. The evidence shows that there were 471 fruit bearing trees and plants: 13 timber trees and 12 Bamboo clusters. Though there is some evidence as to the value of the yield	 this may not be a relevant factor having regard to the principles of valuation appropriate to the case. There is no evidence about the timber value and the fuel value of the trees. Learned District Judge has awarded a sum of Rs.355.85 for the entire tree growth. Having regard to the large number of trees and to the fact that some of them were timber trees	 we think we should award lumpsum of Rs.7	500 under this head. Accordingly	 compensation for the tree growth is enhanced from Rs.355.85 to Rs.7	500. 11. Re: Contention(d) This leaves us with the question whether the benefit of Section 23(2) introduced by the UP Land Acquisition (Amendment) Act 1972 (Act No. 28 of 1972) providing for a solatium is available to the appellant on the ground that the proceedings in appeal were pending as on the date when that provision was introduced. It is to be recalled that by U.P. Land Acquisition (Amendment) Act (Act No. 22 of 1954) Section 23(2) had been deleted from the statute. The preliminary notification was long subsequent to this deletion. The question is whether the introduction or re introduction of Section 23(2) in 1972 would enure to the benefit of the appellant on the premise that rules of construction appropriate to such remedial measures would require their benefit to be extended to pending proceedings. Appellant has also claimed the benefit of the further enhancement of the solatium and the rates of interest under Central Amending Act 68 of 1984. Shri Mukharjee submitted that these amendments	 both by the State Law and the Central Law	 were remedial legislations and would apply to pending actions. Shri Prithviraj	 on the contrary	 submitted that these changes in the law	 brought in by the amended provisions are presumptively prospective except to the extent that they are made expressly or by compelling implication retrospective in the extension of their benefits. Learned Counsel said that application of these provisions even to pending proceedings envisages a principle of retro active application which must expressly be enabled by the statute or is to be inferred as an inevitable implication. 1042 Shri Mukharjee relied upon certain observations of this court in the case of Bhag Singh & Ors. vs Union Territory of Chandigarh	 (See 1985 Suppl. 2 SCR 949). There are some observations at 958 of the report which tend to lend support to Shri Mukharjee. But the matter is pending decision at the hands of a larger bench. In the circumstances	 learned counsel on both sides submitted that the appeal be disposed of on the other points leaving it open to the appellant to agitate Contention (d) after a final pronouncement in Bhag Singh 's case	 if in the light of the said judgment	 this claim or any part of it survives. We accept this submission and reserve liberty to the appellant accordingly. Shri Mukharjee sought to raise another point concerning compensation to be awarded for change of residence under Clause 'fifthly ' in Sec. 23(1); but as this point does not appear to have been raised and urged before the High Court. We think	 we should not permit the appellant to re agitate this question over again in this court. It is also to be observed that no specific ground is taken in this behalf in this appeal either. In the result	 this appeal is allowed in part and while the compensation determined and awarded for the land is left undisturbed	 the compensation awarded for the building and tree growth is enhanced from Rs.57	660 to Rs.2	00	000 and from Rs.355.85 to Rs.7	500 respectively. Appellant shall be entitled to interest at 6% on the enhanced amount of compensation from the date of taking of possession till realisation. Liberty is reserved to the appellant to seek such additional relief on Contention (d) depending upon the ultimate decision in Bhag Singh 's case. The appeal is disposed of accordingly. The appellant shall be entitled to the costs in this appeal. The advocate 's fee fixed at Rs.2	500. N.V.K. Appeal allowed.

% The suit property known as "Gopal Lal Villa" situated on the outskirts of the city of Varanasi was a sprawling 60 years old building	 part of the estate of a Raja	 and vested in the appellant. It was acquired pursuant to preliminary Notification dated 4.7.1959 under the Land Acquisition Act 1894 for the purposes of the Education Department of the Government of Uttar Pradesh. The building was of about 25	000 square feet plinth area comprising 35 rooms	 halls and other appurtenances	 and the 23.66 acres of ground appurtenant to the building	 had 431 fruit and 13 timber trees and 12 bamboo clumps. The appellant claimed compensation of Rs.8	00	580 for the land valuing it at Rs.352 per decimal. Rs.3	50	000 for the building and structures; Rs.41	010 for the tree growth and Rs.5	000 as compensation for change of residence. The Land Acquisition Officer by his Award dated 4.11.1961 1026 under section 11 of the Land Acquisition Act determined the market value of the land at Rs.3	31	340 valuing it at Rs.140 per decimal; of the building and superstructure at Rs.57	660 and of the tree growth at Rs.355.83. Being aggrieved with the aforesaid determination of compensation the appellant did not accept the offer contained in the Award	 and sought for a reference under section 18 of the Act to the Civil Court. The District Court enhanced the market value of the land to Rs.4	73	200 i.e. from Rs.140 to Rs.200 per decimal and left the valuation of the building and the tree growth undisturbed. The High Court affirmed the Award of the District Court and dismissed the appellant 's claim for further enhancement. In the appeal to this Court	 it was contended on behalf of the appellant that the claim of Rs.352 per decimal was not accepted and that the High Court in affirming the valuation of the land at a mere Rs.200 per decimal overlooked certain settled principles of valuation. It adopted the District Judge 's valuation which was the average of the valuation reflected in Ext. 2 and Ext. 19 while the higher of the two figures indicated by Ext. 2 should have been adopted. It was further contended that the appellant was entitled to solatium and interest at higher rates in view of the re introduction of section 23(2) in 1972 by the U.P. Land Acquisition (Amendment) Act	 1972 and under the Central Amendment Act 68 of 1984. On behalf of the respondent it was contended that the changes in law brought about by the State Amendment Act No. 28 of 1972 and the Central Amending Act 68 of 1984 are presumptively prospective except to the extent that they are made expressly or by compelling implication retrospective in the extension of their benefits. On the question whether: (1) ^ HELD: 1.(i) The determination of market value of a piece of land with potentialities for urban use is an intricate exercise which calls for collection and collation of diverse economic criteria. [1033C D] (ii) The market value of a piece of property for purposes of section 23 of the Land Acquisition Act is stated to be the price at which the property changes hands from a willing seller to a willing	 but not too anxious a buyer	 dealing at arm 's length. [1033D] (iii) Prices fetched for similar lands with similar advantages and potentialities under bonafide transactions of sale at or about the time of the preliminary notification are the usual	 and indeed the best	 evidences of market value. Other methods of valuation are resorted to if the evidence of sale of similar lands is not available. [1033E F] (iv) Prices fetched for smaller plots cannot form safe bases valuation of large tracts of land as the two are not comparable properties. [1034E] Collector of Lakhimpur vs B.C. Dutta	 AIR 1971 SC 2015; Mirza Nausherwan Khan & Anr. vs The Collector (Land Acquisition)	 Hyderabad	 ; ; Padma Uppal etc. vs State of Punjab & Ors. 	 ; and Smt. Kaushalya Devi Bogra & Ors.v. The Land Acquisition Officer	 Aurangabad & Anr.	 ; 	 referred to. (v) However	 if it is shown that the large extent to be valued does admit of and is ripe for use for building purposes; that building plots that could be laid out on the land would be good selling propositions and that valuation on the basis of the method of a hypothetical lay out 1028 could with justification be adopted	 then in valuing such small	 laid out sites the valuation indicated by sale of comparabe small sites in the area at or about the time of the notification would be relevant. [1034G H] (vi) In a case such as the above	 necessary deduction for the extent of land required for the formation of roads and other civic amenities; expenses of development of the sites by laying out roads	 drains	 sewers	 water and electricity lines	 and the interest on the outlays for the period of deferment of the realisation of the price; the profits on the venture etc. are to be made. [1034H; 1035A B] Sahib Singh Kalha & Ors. vs Amritsar Improvement Trust and Ors.	 referred to. (vii) Prices fetched for small plots cannot directly be applied in the case of large areas	 for the reason that the former reflects the 'retail ' price of land and the latter the 'wholesale ' price. [1035B] (viii) Subsequent transactions which are not proximate in point of time to the acquisition can be taken into account for purposes of determining whether as on the date of acquisition there was an upward trend in the prices of land in the area. [1035C] (ix) Where it is shown that the market was stable and there were no fluctuations in the prices between the date of the preliminary notification and the date of such subsequent transaction	 the transaction could also be relied upon to ascertain the market value. (a) When there is evidence to the effect that there was no upward surge in the prices in the interregnum. (b) The burden of establishing this would be squarely on the party relying on such subsequent transaction. [1035C D	G] State of U.P. vs Major Jitender Kumar	 referred to. In the instant case	 the appellant did not endeavour to show that between the date of preliminary notification i.e. 4.7.1959 and the date of Ext. 24 i.e. 18.8. 1960 there was no appreciation in the value of land in the area. Therefore	 Ext. 24 cannot be relied upon as affording evidence of the market value as on 4.7.1959. [1035G H] (xi) The valuation of land made in the present case does not call for or justify any upward revision at all. (a) There is no justification to interfere with the determination of the market value of the land approved by the High Court. [1036C D] 1029 In the instant case Rs.200 per decimal for the large extent of the acquired land works out to 40% of the "retail" price even if Rs.500 is taken as the 'retail ' price. That apart	 in the case of land with potentialities for a more profitable use it is necessary to acknowledge	 and make due allowance for	 the possibility that the land might not be applied for the prospective use at all or not so applied within a reasonable time. [1036H; 1037A B] Bombay Improvement vs Mervanji Manekji Mistry	 AIR 1926 Bombay 420 referred to. 2.(i) Usually land and building thereon constitute one unit. Land is one kind of property; land and building together constitute an altogether different kind of property. The latter must be valued as one unit. [1037C D] (ii) However	 where	 the property comprises extensive land and the structures standing do not show that full utilisation potential of the land is realised it might not be impermissible to value the property estimating separately the market value of the land with reference to the date of the preliminary notification and to add to it the value of the structures as at that time. [1037D E] (iii) By the above method	 building value is estimated on the basis of the prime cost or replacement cost less depreciation. The rate of depreciation is	 generally	 arrived at by dividing the cost of construction (less the salvage valued at the end of the period of utility) by the number of years of utility of the building. [1037E F] (iv) The factors that prolong the life and utility of the building	 such as good maintenance	 influence and bring down the rate of depreciation. [1037F] In the instant case	 the estimate of the proper market value of the building has not received the requisite attention both before the High Court and the District Court. It is no doubt true that the Valuation Report	 Ext. I	 was prepared on 20.7. 1960 one year after the date of the preliminary notification. But the extent of the built area was about 25	000 sq. There is no evidence to suggest that the rates mentioned and adopted in Ext. I were not rates valid for a spread out period. No case was made out that the building had lost its utility and that the only mode of valuation appropriate to the case was one of awarding merely the salvage value. The building	 according to the evidence was quite 1030 strong though about 60 years old at the time. The appropriate thing to do would have been to set aside the award in so far as the valuation of the building is concerned and remit the matter for a fresh determination of its market value as on 14.7.1959. However	 in the interest of justice it would be proper to make some ready and rough estimate drawing such sustenance as the evidence on record could afford and impart a quietus to this vexed litigation. Accordingly	 the compensation for the buildings and structures is enhanced from Rs.57	660 to Rs.2	00	000. [1038G H; 1039D G; 1040G] 3. Where land is valued with reference to its potentiality for building purposes and on the basis of prices fetched by small sites in a hypothetical lay out the tree growth on the land cannot be valued independently on the basis of its horticultural value or with reference to the value of the yield. This principle	 however	 does not come in the way of awarding the timber value or the salvage value of the tree growth after providng for the cost of cutting and removing. [1040G H; 1041A] In the instant case	 the evidence shows that there were 471 fruit bearing trees and plants	 13 timber trees and 12 bamboo clusters. Though there is some evidence as to the value of the yield	 there is no evidence about the timber value and fuel value of the trees. The District Judge has awarded a sum of Rs.355.85 for the entire tree growth. Having regard to the large number of trees and to the fact that some of them were timber trees	 it would be appropriate to award a lump sum of Rs.7	500 under this head. The compensation for tree growth is accordingly enhanced from Rs.355.85 to Rs.7	500. [1041A C] 4. By the U.P. Land Acquisition (Amendment) Act	 1954	 Section 23(2) had been deleted from the statute. It was re introduced by the U.P. Land Acquisition (Amendment) Act 1972. The preliminary notification for the acquisition was issued subsequent to the deletion. Whether re introduction of sub section (2) would enure to the benefit of the person whose land is acquired on the ground that proceedings in appeal were pending on the date of introduction of that provision	 and availability for further enhancement of the solatium and rates of interest under the Central Amendment Act 68 of 1984 are left open with consent of counsel to be agitated after final decision in Bhag Singh vs U. T. of Chandigarh	 by a larger Bench of this Court. [1041E F; 1042B] 5. The point concerning compensation to be awarded for change of residence under clause 'fifthly ' in section 23(1) does not appear to have been raised and urged before the High Court. No specific ground 1031 has also been taken in this behalf in the appeal before this Court. The appellant should not	 therefore	 be permitted to re agitate this question over again in this Court. [1042D]