Some random statistics about the presumed "BitPay.com wallet" in this site:
http://www.walletexplorer.com/wallet/BitPay.comFrom the first entry on 2011-07-02 to about 2014-12-02:
About 690'500 transfers into the addresses in this "wallet", adding to about +1'270'000 BTC
Largest single input into those addresses: +9483.46000000 BTC on 2012-06-24 00:39:05
( transaction d4f7fbbf92f4a3014a230b2dc70b8058d02eb36ac06b4a0736d9d60eaa9e8781 )
There were
47 inputs of at least 2000 BTC
137 inputs of at least 1000 BTC
316 inputs of at least 500 BTC
578 inputs of at least 250 BTC
In 2012 there were two inputs of ~230 BTC from addresses in the "SilkRoadMarketplace" cluster.
Also one input of ~590 BTC from wallet "Btcst.com-pirateat40".
KnC miners made several large inputs between Nov/2013 and Feb/2014 (buying equipment for their centers?)
The payment for the 0.5 M$ home of BFL's Josh Zerlan, which was reported as being made through Bitpay
http://www.kmbc.com/news/bitcoins-used-to-buy-johnson-county-home/26078516seems to be this 1060 BTC transaction on 2014-04-28 22:08:49 UTC :
http://www.walletexplorer.com/txid/470dd9660d62b60ce8451c22392ba119b1c0b97d0927d6d5ef3ee0c2da043585There were ~633'000 inputs of 1.0 BTC or less; ~440'000 of them were in 2014.
It would be more informative to use dollar amounts instead of BTC amounts, since the price varied so much in that time span. Coming soon.
However, as observed before, the BTC amounts of the largest inputs seem to be roughy constant over time.