This is only an example that you can adapt to your needs. The job involves placing 600 large blocks. We initially assume that we can place 3 blocks per day. The job started April 1st. In *A2* we enter:

4/1/2015

In *B2* we enter the formula:

**=A2+600/3** our initial estimate of the end date.In *C2* we enter today's date and in *D2* we enter the total progress to date. (Both *C1* and *D1* can be updated daily.)

In *D3* we enter the formula:

**=D2/600** This is our percent complete.

In *E2* we enter a formula to re-evaluate the productivity based on actual data:

**=D2/(C2-A2)**

Finally in *F2* we can enter our latest, best, estimate of the completion date:

**=TODAY()+(600-D2)/E2** Here is a sample:

In this sample, we initially thought it would take 200 days to place the blocks. We now see that the actual productivity is only around **2.2** compared to **3.0** This allows us to re-estimate the completion date based upon the actual productivity and the number of blocks that still must be placed.