Around December,1944 for # 137700.as the year 1945 started with serial number 137800.
No known published sn data
what year was a Hitachi excavator built with serial number 133 2797
It was built in 1959!
it would appear there are too many numbers in your serial number.....................
about 1918
about 1905
about 1918
about 1929
1917
1924
Assuming this is an upright (vertical) piano, the serial 261236 would belong to a unit built sometime in 1936. If the serial number belongs to a grand instead, it would have been built in 1984.
According to the serial number provided, it was built in 1942. According to bluebookofpianos dot com, it was built in 1995.