=LEFT(A1,8)&"-"&RIGHT(A1)
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David Biddulph

Jacqueline wrote:
Hi all,

I usually face set of numbers that consists of 9 numbers. E.g
123456789, 987654321.

I'm figuring how to add a hyphen between the 8th and 9th character
which will enable the numbers to look something like 12345678-9,
98765432-1. The set of numbers of cos varies day to day.

Pls help. Appreciate if anyone could enlighten me. =))