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:
| No. in series | No. in season | Family/families | Location(s) | Original air date |
| --- | --- | --- | --- | --- |
| US1 | 1.0 | The Jeans Family | Denver, CO | 1January2005 |
| US2 | 2.0 | The Bullard Family | Aurora, CO | 24January2005 |
| US3 | 3.0 | The Orm Family | Santa Clarita, CA | 31January2005 |
| US4 | 4.0 | The Wischmeyer Family | Colorado | 7February2005 |
| US5 | 5.0 | The Weston Family | Florida | 14February2005 |
| US6 | 6.0 | The Bailey Family | N/A | 21February2005 |
| US7 | 7.0 | The Gorbea Family | California | 28February2005 |
| US8 | 8.0 | The Ririe Family | Thousand Oaks, CA | 21March2005 |
| US9 | 9.0 | The Burnett Family | N/A | 18April2005 |
Question:
What's the season number of the episode with series number US6?
Answer:
6.0