Except one stay ( Sheraton Firenze ) all the time upgraded to a suite this year so far. One time used 2 SNAs to make an upgrade sure.
Burned 8 SNAs for upgrades at a hotel where I would be upgraded anyway, just for using them...
Another 9 SNAs are used for two upcoming stays at the end of the year and at least 1 SNA will expire or 5 or 6 or 10. Who knows...

So my ratio is near 95 %.