A system for determining a quantity of transported fluid, comprising an interface configured to receive a plurality of measured parameters corresponding to measurements directed to a fluid within a conduit at different measurement times while the fluid is transported; a measured parameter receiver for obtaining the plurality of measured parameters relating to the fluid within the conduit at the different measurement times during at least a predetermined time interval; a measured parameter combiner for combining the measured parameters relating to the predetermined time interval, using a full flow rate calculation, to obtain a first quantity indicative of an amount of fluid that has been transported through the conduit during the predetermined time interval; a time interval divider for dividing the predetermined time interval into a plurality of subintervals corresponding to respective quantity calculation periods (QCPs); a parameter associating unit for associating at least one averaged parameter with each of the subintervals, wherein the parameter associating unit comprises an averaged parameter determiner for determining an averaged parameter for a subinterval based on a plurality of the measured parameters having measurement times that fall within the subinterval; a parameter corrector for determining a corrected value for at least one of the averaged parameters; and a quantity corrector for determining a corrected value for the first quantity based on the corrected value for said at least one of the averaged parameters, wherein the quantity corrector comprises: a first averaged parameter combiner for combining the averaged parameters associated with the subintervals, using a factored flow rate calculation, to obtain a first estimated quantity indicative of the amount of fluid that has been transported through the conduit during the predetermined time interval; and a second averaged parameter combiner for combining the averaged parameters associated with the subintervals, using the factored flow rate calculation, wherein said at least one of the averaged parameters is replaced by the corrected value, to obtain a second estimated quantity indicative of the amount of fluid that has been transported through the conduit during the predetermined time interval, wherein the quantity corrector is configured to compare the first estimated quantity to the second estimated quantity. a first averaged parameter combiner for combining the averaged parameters associated with the subintervals, using a factored flow rate calculation, to obtain a first estimated quantity indicative of the amount of fluid that has been transported through the conduit during the predetermined time interval; and a second averaged parameter combiner for combining the averaged parameters associated with the subintervals, using the factored flow rate calculation, wherein said at least one of the averaged parameters is replaced by the corrected value, to obtain a second estimated quantity indicative of the amount of fluid that has been transported through the conduit during the predetermined time interval, wherein the quantity corrector is configured to compare the first estimated quantity to the second estimated quantity. <EOS>