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:
| Start month | End month | Cover | Spine | Indicia | Masthead | Number of issues |
| --- | --- | --- | --- | --- | --- | --- |
| Oct–50 | Aug–58 | Galaxy Science Fiction | Galaxy Science Fiction | Galaxy Science Fiction | Galaxy Science Fiction | 94.0 |
| Sep–58 | Oct–62 | Galaxy Magazine | Galaxy Magazine | Galaxy Magazine | Galaxy Magazine | 27.0 |
| Dec–62 | Dec–65 | Galaxy | Galaxy | Galaxy Magazine | Galaxy Magazine | 19.0 |
| Feb–66 | Sep–68 | Galaxy | Galaxy | Galaxy Magazine | Galaxy Magazine | 18.0 |
| Oct–68 | Oct–69 | Galaxy Science Fiction Magazine | Galaxy | Galaxy Magazine | Galaxy Magazine | 12.0 |
| Nov–69 | Jan–72 | Galaxy Science Fiction Magazine | Galaxy | Galaxy Magazine | Galaxy Science Fiction Magazine | 20.0 |
| Mar–72 | Mar–72 | Galaxy Magazine | Galaxy | Galaxy Magazine | Galaxy Science Fiction Magazine | 1.0 |
| May/Jun–72 | Jan–73 | Galaxy Magazine | Galaxy Science Fiction | Galaxy Magazine | Galaxy Science Fiction | 5.0 |
| Mar/Apr–73 | Mar/Apr–73 | Galaxy | Galaxy | Galaxy Magazine | Galaxy Science Fiction Magazine | 1.0 |
| May/Jun–73 | Nov–73 | Galaxy | Galaxy | Galaxy | Galaxy Science Fiction | 5.0 |
| Dec–73 | Dec–73 | Galaxy Science Fiction | Galaxy | Galaxy | Galaxy Science Fiction Magazine | 1.0 |
| Jan–74 | Jan–75 | Galaxy | Galaxy | Galaxy | Galaxy Science Fiction Magazine | 13.0 |
| Feb–75 | Jan–76 | Galaxy | Galaxy | Galaxy Incorporating Worlds of If | Galaxy Science Fiction Magazine | 9.0 |
| Feb–76 | Oct–77 | Galaxy Science Fiction | Galaxy Science Fiction | Galaxy Incorporating Worlds of If | Galaxy Science Fiction | 16.0 |
| Nov–77 | Dec-77/Jan–78 | Galaxy | Galaxy | Galaxy Incorporating Worlds of If | Galaxy | 2.0 |
| Feb–78 | Oct–79 | Galaxy Science Fiction | Galaxy Science Fiction | Galaxy Incorporating Worlds of If | Galaxy Science Fiction | 10.0 |
| Summer–80 | Summer–80 | Galaxy | Galaxy | Galaxy | Galaxy | 1.0 |
Question:
How many issues end on jan–72?
Answer:
20.0