About 1000, but I hung on in certain generations because I got close to completing challenges that rewarded rare burn cards such as Titans, Map Hacks etc. so I ensured I completed the challenges even though I could have regened 10-15 games sooner than I actually did. If I went straight for the Gen 10, I personally believe I would have accomplished it significantly sooner.
I was basically at 1,000 when I hit 10th gen, but I'm not quite at 50 yet! I'll be sure to take note of where I'm at when I do.