Field help (AMKTYPMSK) 

The screen is firstly defined by its type, which can be :

The first three types (header, tab, dialog box) require the additional entry of a number of lines and columns remembering that the tab tiles takes 1 line, the section outline takes 1/2 line per line and that the maximum is 28 lines, 112 columns (88 columns if there is a quick select list).

These two fields (lines, columns) are considered as part of the setup. The values of these fields are not decreased by the integration of patch, except for the number of lines if any specific activity code has been found (in the blocks or in the fields).