replace column if exists

[#1]

hi,

i had a question

i had a table like that:

Client2013     Client2014     Client2015

QUICK               -                   Mcdo

Flunch              KFC               QUICK

Eli                    -                         -

Elo                    Youk                    -

Mcdo                    -                    QUICK

i'd like to have a new column with conditions if there is somthing in client 2014 replace in client2013 and if exists client2015 replace client2014(with replace client2013 if exist)

to resume, the result should be:

NvClients

Mcdo

QUICK

Eli

Youk

QUICK

how can i do? THANKS a lot and sorry for my bad english

[#2]

Sorry but error in expression : Len takes 1 parameter..

[#3]

Sorry but i have an other problem..

That's ok when in the fields Client2013 there is a number in the field.

But when there is only letters "quick" for example that not work

Client2013     Client2014     Client2015   nvclient

QUICK               -                   Mcdo          -

Flunch22            -                    -             Flunch22

..

thanks