IF statement returns a result if cells are blank. How can I remove that?

[mcintoshmc]

This formula works, but if all cells are blank, it will show as completed because they are indeed equal to each other. How can I return a blank result, if all cells are blank?

=IF((AND($T17=$U17,$V17=$W17,$X17=$Y17)),"Completed","Not Yet")

 

[mcintoshmc]

okay, I came up with this, but still not quite working

IF(ISBLANK($L17),"",IF((AND($T17=$U17,$V17=$W17,$X17=$Y17)),"Completed","Not Yet"))

 

[Fluff]

Maybe
=IF($T17&$U17&$V17&$W17&$X17&$Y17="","",IF(AND($T17=$U17,$V17=$W17,$X17=$Y17),"Completed","Not Yet"))