In reply to dave_59:
Thanks Dave . Using %e / %g gives the intended result .
The issue seems to be due to limitations with %f ( which Displays real numbers in a decimal format )
LRM says output for decimal format depends on the Size of the expression .
LRM 21.2.1.3 :: " For example, the result of a 12-bit expression would be allocated four characters when displayed in decimal format because the largest possible value for the expression is 4095 (decimal). "
How is the real data type treated ( Size wise ) ?