The scaling represents a magnification factor, or minimization factor, of the document to be printed, along with the included graphic elements like letters or embedded images, which will be magnified (stretched), or minimized (upset) by a factor
scaling / 100
For instance, a scaling of 108 means that a picture document of 100 x 50 mm edge length is stretched by 108% of its original size, thus it will later measure 108 x 54 mm .
A deviation from the normal scaling default value of 100 (100% means original size) only makes sense for image documents like Bitmaps (*.bmp), as their original size is – unlike text documents in text editing programs - not bound, to pre-set paper formats like A4, A5 etc. It makes no sense to display a text document, whose lines and line breaks are adapted to A4, at a modified size. For this reason, MS Word, for example, refuses such requests by displaying the following warning message:
On the other hand, under some circumstances, it can make sense to print an image document which is just 2% too large to fit the next smaller paper format, on 98% of its original size.
However, in general, we advise you not to use other scaling values than the default value of 100.