18. Interest expense

Interest expense 1 January - 31 December 2015 1 January - 31 December 2014
Sell buy-back transactions 68,209 105,975
Own debt instruments issued 37,655 15,676
Bank loans taken by PZU Group entities 4,394 8,908
Investment contracts with guaranteed and fixed terms and conditions 6,477 16,609
Other 698 117
Total interest expense 117,433 147,285