The estimated production curves for the YORK Band Instruments are based on instruments for which serial number and date of manufacture are known. In addition, an estimation of monthly output in the early part of the century and a correlation of serial numbers with patent dates which appear on certain York instruments has been taken into account. Six individual yearly production rates are plotted above, and it is projected that the closest estimate of the actual year of manufacture can be estimated by establishing a range of possible dates from these production curves. For example, an instrument with the serial number 28000 could have been made between the years 1904 and 1910, depending on the actual rate of production. It is believed that the yearly production rate of 2750 instruments comes the closest to meeting all the criteria used to establish this table, but variations in yearly production are not known, so the range of dates is probably the safest way to "guesstimate" the date of manufacture.

Year Manufactured 2500 Insts./Yr. 2700 Insts./Yr. 2750 Insts./Yr. 2800 Insts./Yr. 2900 Insts./Yr. 3000 Insts./Yr.
1897 9500 1300 ---- ---- ---- ----
1898 12000 4000 2000 ---- ---- ----
1899 14500 6700 4750 2800 ---- ----
1900 17000 9400 7500 5600 1800 ----
1901 19500 12100 10250 8400 4700 1000
1902 22000 14800 13000 11200 7600 4000
1903 24500 17500 15750 14000 10500 7000
1904 27000 20200 18500 16800 13400 10000
1905 29500 22900 21250 19600 16300 13000