Retrieve last non blank value in a list

[Tornado1981]

Hi,
I would really appreciate if u help me on solving this
I want a formula in each cell in column C to do this :
(Taking C5 as an example)
Test if there is a value in A5 .. if not found, then leave C5 blank .. else, test if there is a value in ($C$1:C4) .. and if found, then add the last value found in ($C$1:C4) to A5 and subtract B5 from the result .. else [ no values found in ($C$1:C4) ], then subtract B5 from A5

Thank u so much

Note : I used the offset function to retrieve the last non blank value in ($C$1:C8)

 

[Tornado1981]

Dear Aladin,
Another problem here
When I enter a value in B12 and C12&D12 are blank, E12 stills the same as E11, while i want it to be E11+C12+D12-B12
Any suggestions ?

 

[Tornado1981]

Any suggestions here ?

 

[Aladin Akyurek]

Dear Aladin,
Another problem here
When I enter a value in B12 and C12&D12 are blank, E12 stills the same as E11, while i want it to be E11+C12+D12-B12
Any suggestions ?

E3, just enter and copy down:

=IF(MATCH(BigNum,$A$3:$A$12)>=ROWS($D$3:D3),
   IF(OR(ISNUMBER(LOOKUP(BigNum,$E$2:E2)),N(D3)),
    SUM(LOOKUP(BigNum,CHOOSE({1,2},0,
      LOOKUP(BigNum,$E$2:E2))),C3,D3,-B3),""),"")

The rule has become:If a figure is available in E[i-1] or D, proceed to sum E[i-1],C,D,and -B.