Just a slight tweak to formula ..
(but think the earlier one would also work as well)

Put in F2 and array-enter, i.e. press CTRL+SHIFT+ENTER:

=INDEX(B2:E2,MATCH(MAX((B$1:E$1)*(B2:E2<"")),(B$1 :E$1)*(B2:E2<""),0)) -
INDEX(B2:E2,MATCH(MIN(IF((B$1:E$1)*(B2:E2<"")<0, (B$1:E$1)*(B2:E2<""))),(B
$1:E$1)*(B2:E2<""),0))

Copy F2 down to F5
--
Rgds
Max
xl 97
---
GMT+8, 1° 22' N 103° 45' E
xdemechanik <atyahoo<dotcom
----