If(OR) Function with CONCATENATE

Hi guys,

Tried building a formula yesterday but power went in the office yesterday and lost it and struggling to get it to work again,

=IF(OR('Data Input Tab'!E27="",'Data Input Tab'!E28=""),"Insufficient data input to make calculation",CONCATENATE(" your ",'Data Input Tab'!D24," fund has ",IF('Data Input Tab'!E27<E28,"underperformed the sector in the 0-12 month period","outperformed the sector in the 0-12 month period"))),

This formula works fine but then I want to basically duplicate this and search different cells, however without the (" your ",.........fund has ", aspect of the formula. e.g.

=IF(OR('Data Input Tab'!E27="",'Data Input Tab'!E28=""),"Insufficient data input to make calculation",CONCATENATE(" your ",'Data Input Tab'!D24," fund has ",IF('Data Input Tab'!E27<E28,"underperformed the sector in the 0-12 month period","outperformed the sector in the 0-12 month period"))),IF(OR('Data Input Tab'!F27="",'Data Input Tab'!F28=""),"Insufficient data input to make calculation",CONCATENATE(IF('Data Input Tab'!F27<F28,"underperformed the sector in the 13-24 month period","outperformed the sector in the 13-24 month period")))

However this just returns a FALSE value so I'm clearly missing something...

Any of you experts spot the mistake?

Any help greatly appreciated.

Cheers

Rick