Yield analysis data can be stored in data sets. Yield data from previous run can easily be viewed without running yield analysis again.
For example, see a simple filter response below.
Then when running yield analysis, make sure the option highlighted below is checked.
After you run the yield, you will see the yield results on your graphs. Additionally, notice the Yield_DS0 data set now in the project. This is storing the yield analysis data.
Now if you closed and reopened the project, the yield data is no longer there, even after you simulate.
For quick simulations, you could run the yield analysis again. For longer simulations, you might prefer to restore the yield data from the previous runs. To do, this right click on the yield data set and select Show Results and the yield data will be back on your graph.