question - in this block chain I've observed that block are not being generated at the advertised rate.
There is no such thing as an "advertised rate".
Block: 42105,Target: 69.91 GH/s, Hashrate: 9.81, 9.30, 9.27 GH/s, Performance: 20.41%
Diff: 1953.27040885, next: ~488 (confidence 47%) - Last Retarget: 56.33 hrs ago, change in 375 blocks (~61.25 hrs)
Expect to see blocks on average every 10 minutes for now, until either difficulty changes in 2-3 days, or hashrate increases back up to the target.
is there some mathematical formula that can be used to calculate the expected number of blocks that will be released in to the black chain based on current difficulty and hashrate as of last adjustment and if so - does the original specs for block times weigh into this calculation. I am working on software that needs to calculate the number of blocks that will be introduced into the blocks chain over the the forthcoming 24 hours period.
720*(average-hashrate/target-hashrate)
in the above example 720*(9.81/69.91) = 101 blocks per 24 hours
edit: http://api.bitmark.co gives you all the info you need
thanks - one other question for you.
if I have 10% of the network hash if it reasonable to assume I will get 10% of the blocks (over some time) - regardless of difficulty?