The short answer is not much. I determined this several years ago at my cottage on the Saint Lawrence River.
First, I plotted on the x-axis the actual sales for over 100 stores operated by a large grocery chain in Florida.
Next, I plotted two different values for each center on the y-axis: a) the center’s occupancy rate and b) the center’s asking rental rate.
If the sales were correlated with either item then the (x,y) points would follow a straight line. Unfortunately, the plot looked like a shotgun blast. There was no correlation between the grocery anchor’s sales and either center’s rents or occupancy level. In other words, the sales did not convey any information about the rest of the center.
So, the next time some genius goes on and on about how good their center is because the grocery anchor or any other anchor has “high sales”, just let them know that there is no correlation with anything meaningful. Now you are the genius.
Onward!