3SThe valuer shall then ascertain the mean of the average prices so calculated for the 3 preceding years for regular cast ewes and for lambs, respectively. The figures so ascertained or ascertained, in a case to which paragraph 4 below applies, in accordance with that paragraph, are in this Part of this Schedule referred to as the “3-year average price for regular cast ewes” and the “3-year average price for lambs”.