other income ( expense ) , net items recorded to other income ( expense ) , net arise from transactions and events not directly related to our principal income earning activities . the detail of other income ( expense ) , net is presented in note 24 , supplemental information , to the consolidated financial statements . 2016 vs . 2015 other income ( expense ) , net of $ 58.1 increased $ 10.8 primarily due to lower foreign exchange losses , favorable contract settlements , and receipt of a government subsidy . the prior year included a gain of $ 33.6 ( $ 28.3 after-tax , or $ .13 per share ) resulting from the sale of two parcels of land . no other individual items were significant in comparison to the prior year . 2015 vs . 2014 other income ( expense ) , net of $ 47.3 decreased $ 5.5 and included a gain of $ 33.6 ( $ 28.3 after-tax , or $ .13 per share ) resulting from the sale of two parcels of land . the gain was partially offset by unfavorable foreign exchange impacts and lower gains on other sales of assets and emissions credits . no other individual items were significant in comparison to fiscal year 2014 . interest expense .
considering the years 2014-2016 , what is the highest interest expense observed?
2016 vs . 2015 interest incurred decreased $ 4.2 . the decrease primarily resulted from a stronger u.s . dollar on the translation of foreign currency interest of $ 6 , partially offset by a higher average debt balance of $ 2 . the change in capitalized interest was driven by a decrease in the carrying value of projects under construction , primarily as a result of our exit from the energy-from-waste business . 2015 vs . 2014 interest incurred decreased $ 5.5 . the decrease was driven by the impact of a stronger u.s . dollar on the translation of foreign currency interest of $ 12 , partially offset by a higher average debt balance of $ 7 . the change in capitalized interest was driven by a higher carrying value in construction in progress . loss on extinguishment of debt on 30 september 2016 , in anticipation of the versum spin-off , versum issued $ 425.0 of notes to air products , who then exchanged these notes with certain financial institutions for $ 418.3 of air products 2019 outstanding commercial paper . the exchange resulted in a loss of $ 6.9 ( $ 4.3 after-tax , or $ .02 per share ) . in september 2015 , we made a payment of $ 146.6 to redeem 3000000 unidades de fomento ( 201cuf 201d ) series e 6.30% ( 6.30 % ) bonds due 22 january 2030 that had a carrying value of $ 130.0 and resulted in a net loss of $ 16.6 ( $ 14.2 after-tax , or $ .07 per share ) . effective tax rate the effective tax rate equals the income tax provision divided by income from continuing operations before taxes . refer to note 23 , income taxes , to the consolidated financial statements for details on factors affecting the effective tax rate . 2016 vs . 2015 on a gaap basis , the effective tax rate was 27.5% ( 27.5 % ) and 24.0% ( 24.0 % ) in 2016 and 2015 , respectively . the change included a 240 bp impact from tax costs associated with business separation , primarily resulting from a dividend declared in 2016 to repatriate cash from a foreign subsidiary , as discussed above in 201cbusiness separation costs . 201d the remaining 110 bp change was primarily due to the increase in mix of income in jurisdictions with a higher effective tax rate and the impact of business separation costs for which a tax benefit was not available . on a non- gaap basis , the effective tax rate increased from 24.2% ( 24.2 % ) in 2015 to 24.8% ( 24.8 % ) in 2016 , primarily due to the increase in and mix of income in jurisdictions with a higher effective tax rate. .