These are my strings

```
2012-13
2013-14
2014-15
2015-16
2016-17
2017-18

```

I my string is `2014-15` as current financial year, I want my next my next financial year as `2015-16`

How can I achieve this with `PHP`? I get these year list form mysql table, but I want next financial year in `php`