TKOF OVER GROSS ON ACCOUNT OF WRONG PASSENGER COUNT.

Narrative

PROB: OVERWEIGHT TKOF. HOW PROB AROSE: LAST MINUTE CHANGE TO WT AND BALANCE DATA DUE TO BOARDING OF ADDITIONAL PAX. CONTRIBUTING FACTORS: INCOMPLETE INFO FURNISHED TO PIC AND PIC FAILURE TO ASK PROPER QUESTIONS TO ENSURE INFO RECEIVED WAS COMPLETE. CORRECTIVE ACTIONS: FUTURE SITUATIONS INVOLVING TIME PRESSED DECISIONS WILL BE SLOWED DOWN TO ENSURE ALL INFO CONCERNING SITUATION IS IN HAND BEFORE DECISION IS MADE. FLT WAS REGULARLY SCHEDULED FROM MIA TO PHL. CREW WAS GIVEN PAPERWORK INCLUDING WT AND BALANCE DATA AS WE ARRIVED AT GATE; ABOUT 40 MINS PRIOR TO DEP. ALL DATA REVIEWED AND WAS NORMAL. GROSS WT WAS 300 LBS OR SO BELOW MAX TKOF WT. AT DEP TIME AGENT CAME TO FLT DECK AND TOLD US HE MUST REMOVE 2 PAX RIDERS FROM FLT DUE TO WT PROBS AND SHOWED US THE TICKETS INVOLVED. WE CHKED OUR COPY OF THE 'WTS' AND DETERMINED WE WERE 300 LBS BELOW MAX TKOF WT AND REQUESTED THAT THE 2 PAX BE LEFT ON ACFT. WE STATED THAT THE TAXI FUEL BURN AS WELL AS HEADWIND COMPONENT AS WELL AS INDICATED GROSS WT PROVIDED MORE THAN ENOUGH LEEWAY TO ACCOMMODATE THESE 2 PEOPLE. FLT DEPARTED AND COMPLETED W/O INCIDENT. ENRTE IT CAME TO OUR ATTN THAT WE HAD NOT 60; BUT 80 PEOPLE ONBOARD THE ACFT. THESE ADDITIONAL PEOPLE WERE THE REAL REASON FOR THE AGENTS CONCERN; AND WHY HE INDICATED A NEED TO REDUCE WT. AT NO TIME WAS THE ADDITIONAL PAX LOAD BROUGHT TO THE CREWS ATTN; JUST A CONCERN WITH THE WT AND THE NEED TO REMOVE THESE 2 PEOPLE. DUE TO THE TIME; AS WE WERE STARTING ENGS; I DID NOT QUESTION THE AGENT AS TO WHY HE WAS CONCERNED WITH JUST 2 PEOPLE. PROPER THINKING WOULD HAVE CLUED ME IN TO THE FACT THAT 2 PEOPLE WERE INSIGNIFICANT AND SOMETHING MORE SUBSTANTIAL WAS THE CAUSE OF THE AGENTS CONCERN. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING: COMPANY PROC CALLS FOR THE PAX AGENT TO CONFIRM THE NUMBER OF PEOPLE ON THE ACFT; THEN ENTER IN THE COMPUTER FOR COMPILATION OF THE WT AND BALANCE NUMBERS WHICH IS DELIVERED TO THE CAPT. CABIN ATTENDANT NORMALLY CONFIRMS THE ACTUAL PAX COUNT AND ADVISES THE CAPT; BUT IN THIS CASE ASSUMED THE PAX AGENT HAD INFORMED THE CAPT. MUCH CONFUSION DURING THE BOARDING PROCESS DUE TO THE LATE BOARDING AND THE FLT WAS RUNNING LATE. HAD DISCUSSED THE PROB WITH HIS FLT MGR AND NO ACTION TAKEN ON THE INCIDENT.