Getting National Heroes - How Long?

[Vicious Love]

Cainehill said:

Of course, that enforced misfortune drops your chance to 2% a turn ( 3% base, +/- 1% per point of luck / misfortune - Misfortune 3 normally means zero chance of getting heroes under normal circumstances ).

But even with Luck-3, I've definately had test games get to at least turn 40 or 50 without a hero, probably real games as well.

I thought the base probability was 1.5%?