Not much to calculate for me, 4 months of the monthly deal. £9.20p
And all of that was during Perblues reign. I have bought one on Gree, but that used Google money Google had randomly given me a while back to spend on the store so not technically money I've spent.
I genuinely feel pity for people that have thrown a lot of money into this broken game and had almost zero thanks by the developers. Some games you feel proud to support with your money and see the company, game and development team blossom and players rewarded for loyalty with a polished game they're happy playing, whereas some you just feel like you've been taken for a ride and rinsed out of as much cash as they can grab without addressing major issues or improving anything.