S. 72 : Carry forward and set off of business losses -Unabsorbed depreciation -Can be set off against sum chargeable to tax as income u/s 68 of the Act – Provision of S.115BBE which barred set off of losses against income determined u/s 68 was effective from 1-4 -2017 and not applicable for the Assessment year 2006 -07 [ S. 32 , 68 71 ,115BBE ]