Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Class | Wheel arrangement | Fleet number(s) | Manufacturer | Serial numbers | Year made | Quantity made | Quantity preserved |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 2-6-2 — oOOO — Mogul | 2-6-2 — oOOO — Mogul | 2-6-2 — oOOO — Mogul | 2-6-2 — oOOO — Mogul | 2-6-2 — oOOO — Mogul | 2-6-2 — oOOO — Mogul | 2-6-2 — oOOO — Mogul | 2-6-2 — oOOO — Mogul |
| D | 2-6-0 | 580–591 | Baldwin | 6851…6909 | 1883 | 12 | 0 |
| D-1 | 2-6-0 | 942–947 | Baldwin | 5636…5701 | 1881 | 6 | 0 |
| D-2 | 2-6-0 | 550–572 | Baldwin | 9544…9688 | 1888–1889 | 23 | 0 |
| D-3 | 2-6-0 | 420–424, 450–547 | Baldwin | 10178…11984 | 1899–1891 | 103 | 0 |
| D-5 | 2-6-0 | 404–418, 426–432 | Baldwin | 10298…11968 | 1899–1891 | 22 | 0 |
| D-6 | 2-6-0 | 400–403 | Rogers | 4842…5433 | 1893–1899 | 4 | 0 |
| K | 2-6-0 | 595–599 | Baldwin | 6590…6629 | 1883 | 5 | 0 |
Question:
what is the quantity made when the class is d-2?
Answer:
23.0