Hi Glen,I copied and pasted from parity web site. I think I know...

Hi Glen,
I copied and pasted from parity web site. I think I know what you are saying but perhaps it is the semantics of the term ratio?

The delta is the ratio between the change in the price of a warrant and the change in price of the underlying. It is between 1 and 0 (for a call) or between 0 and -1 (for a put). It is usually expressed in percentage terms (100% = 1, -100% = -1).


Delta of a Call


The delta of a call is always positive, which means that the direction of the price change is the same as that of its underlying and the delta varies between 0% and 100%. For example, a delta of 45% (0.45) means that, if the underlying increases in value by 1c, the warrant will increase by 0.45c, (adjusted by the ratio). The delta varies continuously with changes in other factors, especially the price of the underlying. In general, the delta of a close-to-the-money option or warrant becomes is close to 50% (0.50), whilst the further out-of-the-money, the more the delta tends towards 0, and the deeper the warrant is in-the-money, the more the delta tends towards 1.