Busfares

[ncr]

Another question for you mass transit freaks out there:

Why do blue non-aircon buses cost more than the red ones? They are both operated by BMTA, and I cannot see any major differences in the level of comfort between them.

I can understand that yellow aircon buses are more expensive than the blue ones, as they are newer and thus probably a bit 'better', if you like.

But what about the normal buses? And how came that differentiation into red and blue ones about, anyway?