With a history of more than 700 years, Shanghai was once the financial center of the Far East regions. Since the reforms that began in 1990s, great changes have taken place in the city. Area 7,037 square km Population Over 20 million   Language The official language in China is Mandarin but distinct dialects are spoken throughout the country. Shanghainese speak Mandarin or Shanghaihua, however most tourist hotels have staff who are fluent in foreign languages. Currency Renminbi (RMB 6.7371 to US$ 1) (as of 15 September 2010)     Service Charge Restaurants and hotels 0~20% Electricity Electricity is supplied at 220 volts, 50 cycles. Telecom The country code of China is 86 and the city code of Shanghai is 021. Network accepted in Shanghai is GSM. Local calls from public coin phones cost RMB0.50 for three minutes or RMB1.00 for five minutes. Useful Numbers Ambulance 120  Police 110  ConsumerCouncil 12315 Overseas Country Code Enquiries 116 Fire Services 119  Time 117  Weather 121 / 221   Tourism Council 64393615 Local and overseas IDD Enquiries 114  Weather 121/221 Pudong Airport Flight Information 96081388 / 38484500 Hongqiao Airport Flight Information 62683659 / 62688918  Time Difference (Take Monday in Shanghai as an example)   Shanghai   8:00 (0) (Monday) New York    19:00 (-13) (Sunday) London (Paris)   0:00 (-8) (Monday) Tokyo   9:00 (+1) (Monday) Sydney   10:00 (+2) (Monday)   Climate Weather in September is generally cool, ranging between 18.6 degree celcius to 23.5 degree celcius (65.5 Fahrenheit to 74.3 Fahrenheit).  Storms with torrential rain can become quite frequent in September. Health and Hygiene Visitors to China are required to fill in a health declaration form at the Customs. Medical facilities are generally adequate in Shanghai. It is advisable to drink only boiled and bottled water.