A total of 75 were built; 55 were built in four batches between 1906 and 1915.

A total of 30 locomotives were built in two batches between 1996 and 2005.

A total of 44 were built, in two batches.

The 120 1854s were built in six batches between 1890 and 1895:

A total of 22 of them were built in two batches.

They were built in three distinct batches leading to detail differences.

This class of unit were built in four different batches for use on different lines.

The class was built in two batches, with the second batch possessing some differences from the first.

Eleven were built in two batches in 1914 and 1925.

Forty locomotives were built to the 9K class, in four batches between 1903 to 1905.