Changing cell References by fixed value

[howard]

I have a series of formula copies from another workbook, but need all the references to be reduced by 10

for Eg for original formula which was copies is =SUM(INDEX(Sheet1!A1671:DG1671,0,104))

I need this automatically reduced by 10 for eg =SUM(INDEX(Sheet1!A1661:DG1661,0,104))

Is there a way in Excel where I can reduce a the values in the range by say 10

Your assistance will be most appreciated

 

[howard]

Hi Fazza

Thanks for the aditional info regarding my posting

Regards

Howard