Find start date of last out of stock period

[Feastie]

Hi guys,

I have a simple table that shows dates across row 2 of my sheet.
Under each date is a stock figure for that date. I want to have a formula that will show the date that was the start of the most recent out of stock period.
I attach a sheet to explain further. The required date would be from column I (19/3/13).

Thanks for any help, Feastie.

[JieJenn]

Ignore this post, I didn't read the question.

[daddylonglegs]

Try this formula

=LOOKUP(2,1/(B3:L3>0)/(C3:M3=0),C$2:M$2)

[Feastie]

Daddylonglegs,

thanks, this works perfectly. Could you enlighten me on the Lookup Vector part please; I don't get what's happening in that middle.
Is it 1 divided by the count of 'greater than zeros' divided by the count of 'equal to zeros'? It seems like there is wizardry going on!!

Once again, thanks, Feastie.