Give you a statement and table with its title in Markdown format, please determine whether the statement is supported or refuted by, or is unrelated to the table. It'a binary classification problem, you should choose the answer between supported and refuted. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| rank | city | population | year of census or estimate | country |
| 1 | mexico city | 8851080 | 2010 | mexico |
| 2 | new york city | 8175133 | 2010 | usa |
| 3 | los angeles | 3792621 | 2010 | usa |
| 4 | toronto | 2791140 | 2011 | canada |
| 5 | chicago | 2695598 | 2010 | usa |
| 6 | houston | 2099451 | 2010 | usa |
| 7 | montreal | 1854442 | 2010 | canada |
| 8 | ecatepec | 1655015 | 2010 | mexico |
| 9 | guadalajara | 1564514 | 2010 | mexico |
| 10 | philadelphia | 1556396 | 2010 | usa |
Title:
list of cities in north america
Statement:
in 2011 year of census or estimate , houston population was less than 1556396
Answer:
refuted