How many turns?

Hi,
I was wondering how many turns there are. I mean I know there're 540, I think, but I was wondering how they are spread over the game. I can't find it anywhere (ie how many turns are with 50years/turn, 25y/t, etc...).
A link would be great, too, I know I saw one somewhere, but can't remember...
Thanks in advance
Markus

4000 BC to 2750 BC - 25 turns, 50 years per turn
2710 BC to 1750 BC - 25 turns, 40 years
1725 BC to 750 BC - 40 turns, 25 years
730 BC to 250 BC - 50 turns, 20 years
260 BC to 1250 AD - 100 turns, 10 years
1255 AD to 1750 AD - 100 turns, 5 years
1752 AD to 1950 AD - 100 turns, 2 years
1951 AD to 2050 AD - 100 turns, 1 year per turn

I believe this is accurate - - -