How exactly are you determining leveling up in stability? the way TK was going about it was that the percent in the quick stats was the chance each turn for that country to level up regarding stability, and if they did, then it would be reset to zero. The percentage is the cumulative percentage of IC they invested in it over the turns.
Seeing as ive had 20% for several turns now and failed to gain stable stability, I now have the feeling that you are using stability as thus: you must get 100% in order to level up. Can I get a ruling on this? I keep looking at my stability, expecting it to level up eventually.