Defined format to show ratios.

I want to express ratios as in
100 Employee in Factory : 10 Employees in Headoffice.

I just need to type 1:10 and it should remain as that without MS Excel considering it as time..

It gives a problem while typing 1:9 , it changes 1:09 which i dont want any suggestions of havingthis format saved in Excel-- fromat cells-Custom..

you could also format the cells or columns as text.