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:
| Rank | Name | Height ft (m) | Floors | Year |
| --- | --- | --- | --- | --- |
| 1.0 | Transamerica Pyramid | 853 (260) | 48.0 | 1972.0 |
| 2.0 | 555 California Street | 779 (237) | 52.0 | 1969.0 |
| 3.0 | 345 California Center | 695 (212) | 48.0 | 1986.0 |
| 4.0 | Millennium Tower | 645 (197) | 58.0 | 2009.0 |
| 5.0 | One Rincon Hill South Tower | 641 (195) | 60.0 | 2008.0 |
| 6.0 | 50 Fremont Center | 600 (183) | 43.0 | 1985.0 |
| 6.0 | 101 California Street | 600 (183) | 48.0 | 1982.0 |
| 8.0 | Chevron Tower | 573 (175) | 40.0 | 1975.0 |
| 9.0 | Four Embarcadero Center | 570 (174) | 45.0 | 1982.0 |
| 10.0 | One Embarcadero Center | 569 (173) | 45.0 | 1971.0 |
| 11.0 | 44 Montgomery Street | 565 (172) | 43.0 | 1967.0 |
| 12.0 | Spear Tower | 564 (172) | 43.0 | 1976.0 |
| 13.0 | One Sansome Street | 550 (168) | 41.0 | 1984.0 |
| 14.0 | One Front Street | 538 (164) | 38.0 | 1979.0 |
| 15.0 | First Market Tower | 529 (161) | 39.0 | 1973.0 |
| 15.0 | McKesson Plaza | 529 (161) | 38.0 | 1969.0 |
| 17.0 | 425 Market Street | 525 (160) | 38.0 | 1973.0 |
| 18.0 | Post Montgomery Center | 500 (152) | 38.0 | 1982.0 |
| 19.0 | 333 Bush Street | 495 (151) | 43.0 | 1986.0 |
| 20.0 | Hilton San Francisco Tower I | 493 (150) | 46.0 | 1971.0 |
| 21.0 | Pacific Gas & Electric Building | 492 (150) | 34.0 | 1971.0 |
| 22.0 | 50 California Street | 487 (148) | 37.0 | 1972.0 |
| 22.0 | 555 Mission Street | 487 (148) | 33.0 | 2008.0 |
| 24.0 | St. Regis San Francisco | 484 (147) | 42.0 | 2005.0 |
| 25.0 | 100 Pine Center | 476 (145) | 33.0 | 1972.0 |
| 25.0 | 45 Fremont Street | 476 (145) | 34.0 | 1978.0 |
| 27.0 | 333 Market Street | 472 (144) | 33.0 | 1979.0 |
| 28.0 | 650 California Street | 466 (142) | 34.0 | 1964.0 |
| 29.0 | 100 First Plaza | 447 (136) | 27.0 | 1988.0 |
| 30.0 | One California | 438 (134) | 32.0 | 1969.0 |
| 31.0 | San Francisco Marriott Marquis | 436 (133) | 39.0 | 1989.0 |
| 32.0 | Russ Building | 435 (132) | 32.0 | 1927.0 |
| 32.0 | 140 New Montgomery | 435 (132) | 26.0 | 1925.0 |
| 34.0 | The Infinity II | 420 (128) | 41.0 | 2009.0 |
| 34.0 | JP MorganChase Building | 420 (128) | 31.0 | 2002.0 |
| 34.0 | The Paramount | 420 (128) | 40.0 | 2002.0 |
| 37.0 | Providian Financial Building | 417 (127) | 30.0 | 1981.0 |
| 38.0 | Three Embarcadero Center | 413 (126) | 31.0 | 1977.0 |
| 38.0 | Two Embarcadero Center | 413 (126) | 30.0 | 1974.0 |
| 40.0 | 595 Market Street | 410 (125) | 30.0 | 1979.0 |
| 41.0 | 123 Mission Street | 407 (124) | 29.0 | 1986.0 |
| 42.0 | 101 Montgomery | 404 (123) | 28.0 | 1984.0 |
| 42.0 | Embarcadero West | 404 (123) | 34.0 | 1989.0 |
| 44.0 | 100 Van Ness Avenue | 400 (122) | 29.0 | 1974.0 |
Question:
What is the average amount of floors of the building that is ranked larger than 30, a year prior to 1977 and an address of 100 Van Ness Avenue?
Answer:
29.0