duct size question

thanks.....got the section replaced that had the hole in it. Unfortunately I don't notice a huge difference at the vent. Gonna check it more tomorrow to see if there's another leak somewhere. It's the furthest vent up front from the furnace but air just barely trickles out of it. Should have more flow than that I think. There's another vent about 18" from it in the step down from the front of the 5er and the difference between the 2 are night and day. I almost have to have another hole in that duct somewhere.