| 2017 | 2016 | 2015 |
| In millions of COP | ||
Deposits | (4,279,316) | (3,878,528) | (2,415,187) |
Debt securities in issue | (1,191,000) | (1,335,192) | (1,057,748) |
Financial borrowings | (672,472) | (723,385) | (454,326) |
Preferred shares | (58,714) | (58,714) | (58,714) |
Borrowings from other financial institutions | (15,860) | (6,345) | (6,836) |
Other interest | (15,624) | (50,936) | (45,130) |
Interest expenses | (6,232,986) | (6,053,100) | (4,037,941) |