22. Income tax

 For the period
Income taxfrom 1 January 2014
to 31 December 2014
from 1 January 2013 to
31 December 2013
Current income tax 869 1 036
Deferred income tax 89 103
Adjustments to income tax from prior periods (10) (1)
Total 948 1 138

 For the period
 from 1 January 2014
to 31 December 2014
from 1 January 2013
to 31 December 2013
Profit before taxation 3 362 4 196
Tax calculated at tax rates in force 639 797
Tax effect of non-taxable income  (20) (47)
Tax effect of expenses not deductible for tax purposes* 339 389
Adjustments to income tax from prior periods  (10) (1)
Income tax expense 948 1 138

* related mainly to the minerals extraction tax.

The rate applied to the taxation of income in accordance with corporate income tax law in force amounted to 19% (for 2013: 19%). The effective tax rate was 28.20% (for 2013: 27.12%). The increase in the effective tax rate in 2014 compared to 2013 was mainly due to the exclusion from costs which are deductible for tax purposes of borrowing costs on an investment loan which was not allocated to capital expenditures.