just look at pool estimate, they are correct, right now at diff 470(was 470 when i made my calculations) you produce only 430 coins per day with 40mh/s
{
"blocks" : 8606,
"difficulty" : 421.10843373,
"networkhashps" : 26503799366,
}
{
"blocks" : 8610,
"difficulty" : 323.82327395,
"networkhashps" : 25943618605,
}
This is why I disregard the difficulty and work with networkhashps.
then the pool is wrong. but their estimate seems correct, at least if you try to mine you get that amount...
the avarage time per block is the problem, because apparently isn't 1 minute, this is due to the diff that change continuously, so 1440000 is the wrong number here