I hope that I am not alone in wanting to offer more support for this excellent service.
2010-01-01 - 2010-12-31: $12.00
2011-01-01 - 2011-12-31: $14.94
2012-01-01 - 2012-12-31: $16.70
2013-01-01 - 2013-12-31: $23.61
2014-01-01 - 2014-12-31: $24.00
2015-01-01 - 2015-12-31: $24.38
2016-01-01 - 2016-12-31: $24.67
2017-01-01 - 2017-01-04: $24.44
That said, it may go up a bit but I feel like it's too confusing to have so many options. Better to have the tier that says you support my work and we both feel good about it. That's what the $36/year option is for.
Besides, if all goes well you'll have the opportunity to pay a bit more for some new hardware I'm launching on Kickstarter on February 7th. Signup for a preview on turntouch.com.