Zeitoin - one doubt

[krixzaok]

Why even with low diff I just can average 6,607 coins per day in 1420 with Kh / s?

I was in doubt as to the USDE is 4.05493180 diff (which is not so minor) and I get mine on average 30,282.0905 coins per day with the same 1420 Kh / s


Zeitoin
{
"blocks" : 122710,
"currentblocksize" : 1000,
"currentblocktx" : 0,
"difficulty" : 4.85277911,
"errors" : "",
"generate" : false,
"genproclimit" : -1,
"hashespersec" : 0,
"networkhashps" : 976993479,
"pooledtx" : 1,
"testnet" : false
}

USDe
{
"blocks" : 137306,
"currentblocksize" : 0,
"currentblocktx" : 0,
"difficulty" : 4.05493180,
"errors" : "",
"generate" : false,
"genproclimit" : -1,
"hashespersec" : 0,
"networkhashps" : 318290578,
"pooledtx" : 0,
"testnet" : false
}