name box not populatimg with all defined names

I have a long list of named ranges, ranging in size from one cell to large tables, all of which have the scope of the workbook. The drop-down "Name Box" in the upper left contains only a subset of the total names (with no obvious pattern to those missing). Does this box have a limit to the number of items or is there something that I must do to get it to update? Using Excel2016 in Windows10 on Microsoft SurfacePro4.

Thanks.