Agents fees

One of many costs that fans don't factor in when a club sells a player for £100k or whatever, and they think the full £100k will be reciprocated in a transfer fee to another club.

 

Also, agent fees are usually paid over the course of of a player's contract so that figure is not just for the players signed in the Summer 2019 and Winter 2020 transfer windows.

FWIW, previous expenditure on agents is:
Feb 2016 - Jan 2017 = £94k
Feb 2017 - Jan 2018 = £101k
Feb 2018 - Jan 2019 = £154k

The FA only started publishing the details partway through the 2015/2016 season so there aren't really any comparable figures for the pre Rahic era other than £5k spent between 1st Oct 2015 and 1st Feb 2016 which does suggest that we did not used to spend as much on agents. However, that period only covers 1 fairly quiet transfer window (Jamie Proctor - free, Wes Thomas - loan) so I'd be wary of reading too much in to it.