hi, this is a issue of very bad organisation of a database file. you should never have null value as you have in this exel file ! thats very bad ! more... these are not really null value because it should be vendred 19/01 value... but for a computer it is a null value... the easiest to do is to use... excel to change your file ! 1) add a column "temp_date" 2) go in the first case of temp_date then 3) calculate your column with the" if"function of excel : if ( clic on comumn date) = '' then new value = (clic on column date - 1 line) else (clic on column date) the only issu is taht the first date msut not be null !! 4) clic down to calcultate all value in your file. 5) then copy/paste to change date column and delete temp column. and never structure a database like that again in your life !!!