price of wheat was higher. sharp ( 2010 ) discusses the issues with constructing the implied ad valorem tariff given the workings of the sliding scale which was recalculated on a weekly basis. note after 1849 a fixed nominal registration duty remained in effect until 1868. chart 5 the volatility of commodity price is measured as a 3 - year moving average of 12 - month inflation rates. from 1960 the monthly commodity prices are sourced from the world bank pink book. prior to 1960 they are sourced from the various indices constructed by the the economist. energy and fertiliser prices are included in the all - items volatility measure from 1963 onwards. chart 6 official consumer price index data from the ons, historical data back to 1950 are sourced from the ons release consumer price inflation, historical data, uk 1950 to 1988. bank of england chart 7 a comparison of the cpi expenditure weights for particular coicop divisions from 1950 ( from the consumer price inflation, historical data, uk 1950 to 1988 ) and the latest data. chart 8 the difference ( in percentage points ) between the annual inflation rates ( quarterly data ) for the all - items cpi and cpi food and non - alcoholic beverages. chart 9 this chart shows the expenditure shares for cpi food and non - alcoholic beverages by equivalised expenditure decile, from the ons dataset : cpi - consistent inflation rate estimates for uk household groups ( democratic weighting ). democratic weighting means that ea h ho sehold ’ s ex end t re shares are we ghted eq all rather than s ng plutocratic we ght ng wh h we ghts ea h ho sehold ’ s ex end t re shares the val e o their overall spending ( which gives richer households a higher weight ). weighting each ho sehold ’ s ex end t re shares eq all s more a ro r ate when looking at how households experience changing prices and costs. chart 10 this chart depicts the changes since january 2020 in the following indicators : the s & p gsci agriculture & livestock index ( in gbp terms ) ; the implied deflator for imported food, beverages & tobacco ; the defra agricultural output rice index ; and cpi food and non - alcoholic beverages. chart 11 the chart shows a bank staff estimate of the contribution of energy effects through the supply chain to inflation rates of different sectors based on supply and use tables in the national accounts. the methodology assumes a gradual, incomplete and asym

and dimsdale ( 2017 ) augmented by some additional data that allow a closer consistency with the current official consumer price index ( cpi ) measure that begins in 1988. the cpi is a weighted average of different prices based on the expenditure patterns o the total ho sehold se tor t t ex l des owner o ers ’ ho s ng osts. from 1209 to 1830, the series is based on the domestic expenditure deflator of clark ( 2010, 2015 ) which is the closest available measure to the current cpi ; from 1830 to 1949, it uses the ons mers ’ ex end t re de lator ased on deane ( 1968 ) ; feinstein ( 1972 ) and sefton and weale ( 1995 ), adjusted to exclude owner - o ers ’ ho s ng osts s ng add t onal information about rents and housing tenure from singer ( 1941 ), swenarton and taylor ( 1985 ) and holmans ( 2005 ) ; from 1949, it uses the long - run cpi index recently produced by the office for national statistics. between 1086 and 1209, the price index is a trend measure based on a more limited set of commodities based on barratt ( 1996, 2001 ), and mayhew ( 2013 ). the data are linked and indexed to 1913 = 100. bank of england alternative measures of consumer prices such as cost of living indices based on the expenditure weights of wage earners can be found in thomas and dimsdale ( 2017 ). lennard and thomas ( 2023 ) construct a measure consistent with the current cpih index which includes owner - occupier housing costs. ( ii ) agricultural prices, 1209 - present the agricultural price index from 1209 up to 1867 is based on the index constructed by clark ( 2004 ) which weights together separate indices for arable, meat, dairy, wool, pasture and wood. from 1867 it uses the chain - linked index of prices of turner ( 1992 ). from 1914 the agricultural price index available in a century of agricultural statisitics ( 1966 ) is used, and is extended to 1988 using various editions of the annual abstract of statistics. from 1988 the data are sourced from the agricultural datasets provided by defra. the data are linked and index to 1913 = 100. chart 3 ( i ) british wheat prices wheat prices from 1545 - 1870 are those constructed by clark ( 2004 ) from a number of underlying historical sources. from 1870 to 1963 the series is