How to add new item in existing Macro's ?

[Rajiv K]

Hello All,

Actually i have an excel (Data) Sheet, when where to do calculation.

in that sheet,there's a cell which is highlighted with some number suppose A when we change it to B  some data are changed but when we again changed it to A  all data get to its orginal state.

i want to add C in that cell.

and A and B are linked with some data table same i want to linked with C.

Please help!!!!!