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:
| Week | Start Date | Type | Tournament | Surface | Town | Country | Continent | Prize Money |
| --- | --- | --- | --- | --- | --- | --- | --- | --- |
| 35 | October 24 | Premier WTA Tour\nChampionships | Sony Ericsson Championships - Istanbul 2011 | Hard | Istanbul | Turkey | Europe | $4,550,000 |
| 8 | March 7 | Premier Mandatory | BNP Paribas Open | Hard | Indian Wells | United States | North America | $4,500,000 |
| 9 | March 21 | Premier Mandatory | Sony Ericsson Open | Hard | Key Biscayne | United States | North America | $4,500,000 |
| 13 | May 2 | Premier Mandatory | Mutua Madrileña Madrid Open | Clay | Madrid | Spain | Europe | $4,500,000 |
| 32 | October 3 | Premier Mandatory | China Open | Hard | Beijing | China | Asia | $4,500,000 |
| 5 | February 14 | Premier 5 | Dubai Duty Free Tennis Championships | Hard | Dubai | United Arab Emirates | Asia | $2,000,000 |
| 6 | February 21 | Premier 5 | Qatar Ladies Open | Hard | Doha | Qatar | Asia | $2,168,400 |
| 14 | May 9 | Premier 5 | Internazionali BNL d'Italia | Clay | Rome | Italy | Europe | $2,000,000 |
| 25 | August 8 | Premier 5 | Rogers Cup presented by National Bank | Hard | Montreal | Canada | North America | $2,000,000 |
| 26 | August 15 | Premier 5 | Western & Southern Financial Group Women's Open | Hard | Cincinnati | United States | North America | $2,000,000 |
| 31 | September 26 | Premier 5 | Toray Pan Pacific Open | Hard | Tokyo | Japan | Asia | $2,000,000 |
| 4 | February 7 | Premier 700 | OPEN GDF Suez | Hard (I) | Paris | France | Europe | $700,000 |
| 10 | April 4 | Premier 700 | Family Circle Cup | Clay | Charleston | United States | North America | $700,000 |
| 11 | April 18 | Premier 700 | Porsche Tennis Grand Prix | Clay (I) | Stuttgart | Germany | Europe | $700,000 |
| 23 | July 25 | Premier 700 | Bank of the West Classic | Hard | Stanford | United States | North America | $700,000 |
| 24 | August 1 | Premier 700 | Mercury Insurance Open | Hard | San Diego | United States | North America | $700,000 |
| 2 | January 10 | Premier 600 | Medibank International Sydney | Hard | Sydney | Australia | Oceania | $600,000 |
| 15 | May 16 | Premier 600 | Brussels Open | Clay | Brussels | Belgium | Europe | $618,000 |
| 18 | June 13 | Premier 600 | Aegon International | Grass | Eastbourne | United Kingdom | Europe | $600,000 |
| 27 | August 22 | Premier 600 | New Haven Open at Yale | Hard | New Haven | United States | North America | $600,000 |
| 34 | October 17 | Premier 600 | Kremlin Cup | Hard (I) | Moscow | Russia | Europe | $1,000,000 |
| 36 | October 31 | International WTA\nTour Championships | Commonwealth Bank Tournament of Champions | Hard (I) | Sofia | Bulgaria | Europe | $750,000 |
| 1 | January 1 | International | Shenzhen Open | Hard | Shenzhen | China | Asia | $500,000 |
| 1 | January 3 | International | Brisbane International | Hard | Brisbane | Australia | Oceania | $220,000 |
| 1 | January 3 | International | ASB Classic | Hard | Auckland | New Zealand | Oceania | $220,000 |
| 2 | January 10 | International | Moorilla Hobart International | Hard | Hobart | Australia | Oceania | $220,000 |
| 4 | February 7 | International | PTT Pattaya Open | Hard | Pattaya City | Thailand | Asia | $220,000 |
| 5 | February 14 | International | Memphis International | Hard (I) | Memphis | United States | North America | $220,000 |
| 5 | February 14 | International | XIX COPA BBVA COLSANITAS | Clay | Bogotá | Colombia | South America | $220,000 |
| 6 | February 21 | International | Abierto Mexicano TELCEL presentado por HSBC | Clay | Acapulco | Mexico | North America | $220,000 |
| 7 | February 28 | International | Malaysian Open 2011 | Hard | Kuala Lumpur | Malaysia | Asia | $220,000 |
| 7 | February 28 | International | Monterrey Open | Hard | Monterrey | Mexico | North America | $220,000 |
| 10 | April 4 | International | Andalucia Tennis Experience | Clay | Marbella | Spain | Europe | $220,000 |
| 11 | April 18 | International | Grand Prix De SAR La Princesse Lalla Meryem | Clay | Fes | Morocco | Africa | $220,000 |
| 12 | April 25 | International | Barcelona Ladies Open | Clay | Barcelona | Spain | Europe | $220,000 |
| 12 | April 25 | International | Estoril Open | Clay | Estoril | Portugal | Europe | $220,000 |
| 15 | May 16 | International | Internationaux de Strasbourg | Clay | Strasbourg | France | Europe | $220,000 |
| 17 | June 6 | International | e-Boks Sony Ericsson Open | Hard | Copenhagen | Denmark | Europe | $220,000 |
| 17 | June 6 | International | Aegon Classic | Grass | Birmingham | United Kingdom | Europe | $220,000 |
| 18 | June 13 | International | UNICEF Open | Grass | 's-Hertogenbosch | Netherlands | Europe | $220,000 |
| 20 | July 4 | International | Collector Swedish Open Women | Clay | Båstad | Sweden | Europe | $220,000 |
| 20 | July 7 | International | Bucharest Open | Clay | Bucharest | Romania | Europe | $250,000 |
| 21 | July 11 | International | Internazionali Femminili di Palermo | Clay | Palermo | Italy | Europe | $220,000 |
| 21 | July 11 | International | NURNBERGER Gastien Ladies | Clay | Bad Gastein | Austria | Europe | $220,000 |
| 22 | July 18 | International | Banka Koper Slovenia Open | Hard | Portorož | Slovenia | Europe | $220,000 |
| 23 | July 25 | International | Mid-Atlantic Women's Tennis Championships | Hard | Washington, D.C. | United States | North America | $220,000 |
| 29 | September 12 | International | Bell Challenge | Hard (I) | Quebec City | Canada | North America | $220,000 |
| 29 | September 12 | International | Tashkent Open | Hard | Tashkent | Uzbekistan | Asia | $220,000 |
| 30 | September 19 | International | Guangzhou International Women's Open | Hard | Guangzhou | China | Asia | $220,000 |
| 30 | September 19 | International | Hansol Korea Open | Hard | Seoul | South Korea | Asia | $220,000 |
| 33 | October 10 | International | Generali Ladies Linz | Hard (I) | Linz | Austria | Europe | $220,000 |
| 33 | October 10 | International | HP Japan Women's Open Tennis 2011 | Hard | Osaka | Japan | Asia | $220,000 |
| 34 | October 17 | International | BGL BNP PARIBAS Luxembourg Open | Hard (I) | Luxembourg | Luxembourg | Europe | $220,000 |
Question:
what is the number of tournaments played on grass?
Answer:
3