Here's a sample of a flagstone/bluestone install calculator. In it, we included production rates for 2 different kinds of stone (square cut vs. irregular) since production times would differ. Typically, we'd only use one or the other on a single job.
Remember: when estimating, your production rate should always be calculated man hours. E.g. - if your 2-man crew can lay 100 sq. ft of flagstone in an 10 hour day, then your production rate is (100 sq. ft / (2 * 10 hrs))
* note - production rates below are for sample only and are not intended for use as recommended production times. Note that these times don't factor any time for daily loading/driving/cleanup.