How to find real text width from dxf file ?

I am developing software that reads from dxf files and processes the
results. I need to know the real height and width of text elements.
With height there is no problem since I can retrieve it. It appears
with code 40 in the dxf file.
The problem is width. I find no means to know the real text width. I
can read from the dxf file the "width / height ratio" ( code 41 ) ,
multiply this ratio by the the height and the number of characters, but
I have been disappointed to see that this is not exact. I have seen for
instance text elements with a "width / height ratio" of 1 with digits
which have a height much greater than width. I usually handle text
elements which display numbers, and their digits are usually drawn
taller than wider, even if they show a width/height ratio of 1 or
similar.
Any help would be appreciated, since I need to know what area these
elements cover.
Thanks