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. | Title | Directed by | Written by | Original Air date |
| --- | --- | --- | --- | --- |
| 1 | "Reunion" | Bryan Spicer | Patrick Massett & John Zinman | January 27, 2003 |
| 2 | "Antarctica" | Perry Lang | Patrick Massett & John Zinman | February 3, 2003 |
| 3 | "Skulls" | Adam Nimoy | Patrick Massett & John Zinman | February 10, 2003 |
| 4 | "Heist" | Rick Kolbe | Rick Kellard | March 10, 2003 |
| 5 | "The Wheel Of Dharma" | R. W. Goodwin | Stephanie Bloch-Chambers & Julie Bean | Unaired in U.S |
| 6 | "Sangraal" | Perry Lang | Gabrielle Stanton & Harry Werksman, Jr. | Unaired in U.S |
| 7 | "Mummy Virus" | Vern Gillum | Rick Kellard & Thania St. John | Unaired in U.S |
| 8 | "Name Of God" | Michael Nankin | Brad Falchuk | Unaired in U.S |
| 9 | "Devil's Child" | Tom Wright | Thania St. John | Unaired in U.S |
| 10 | "Avalon" | Dwight Little | I. C. Rapoport | Unaired in U.S |
| 11 | "The Lost Codex" | Tom Wright | Gabrielle Stanton & Harry Werksman, Jr. | Unaired in U.S |
| 12 | "Eternal" | Fred Gerber | Thania St. John & Chad Hodge | Unaired in U.S |
| 13 | "Helmholtz Resonance" | Larry Shaw | Patrick Massett & John Zinman | Unaired in U.S |
Question:
how many of the episodes did not air in the u.s.?
Answer:
9