• About UBS: (Can read more about UBS from this article in Wikipedia)

UBS is a global financial services company, it is headquartered in Zürich, Switzerland. It is the world's largest manager of private wealth assets, "the world's biggest manager of other people's money", and is also the second-largest bank in Europe, by both market capitalisation and profitability.

• About Mercer: (Can read more from Mercer's website)

As it is claimed itself that Mercer is the global leader for trusted HR and related financial advice, products and services, Mercer has more than 18,000 employees serving clients in over 180 cities and 40 countries and territories worldwide.

The Methodologies that used to generate the ranks:

• UBS's Methodology:

USB conducted its standardized Prices and Earnings survey in 73 international cities in March 2009. The data was collected by several independent observers in each city. In all, more than 30,000 data points were included in the analysis. All amounts were converted into a single currency to ensure that the surveyed prices and earnings could be compared. To compensate for daily exchange rate fluctuations, we used the average exchange rate over the data collection period. An international price comparison needs a common, standard basket of goods and services. As in past studies, the basket of goods and services was based on Western European consumer preferences. Living costs were calculated based on a survey of 154 items in total. They include 122 products and services that are used directly to calculate the reference basket. Apartment rents were classified as high-, mid- and low-priced.

• Mercer's Methodology:

Mercer's Cost of Living survey covers 143 cities across six continents and measures the comparative cost of over 200 items in each location, including housing, transport, food, clothing, household goods and entertainment. It is the world’s most comprehensive cost of living survey and is used to help multinational companies and governments determine compensation allowance for their expatriate employees.

In Mercer’s survey, New York is used as the base city for the index and scores 100 points, all cities are compared against New York and currency movements are measured against the US dollar. Tokyo scores 143.7 points and is nearly three times as costly as Johannesburg with an index score of 49.6.

The period from March 2008 to March 2009 has been characterised by an unprecedented economic downturn. The global economic crisis has had a direct impact on the Cost of Living indices in the various locations covered by Mercer, and hence on the resulting Cost of Living rankings.

Ranks in 2009:

• UBS's rank:

2009    2008    Cities

1	2	Oslo
2	6	Zurich
3	4	Copenhagen
4	7	Geneva
5	8	Tokyo
6	5	New York
7	9	Helsinki
8	13	Vienna
9	10	Paris
10	3	Dublin
11	15	Munich
12	40	Caracas
13	16	Frankfurt
14	11	Luxembourg
15	21	Los Angeles
16	12	Stockholm
17	23	Rome
18	28	Lyon
19	34	Dubai
20	19	Brussels
21	1	London
22	26	Barcelona
23	14	Amsterdam
24	38	Singapore
25	18	Chicago
26	22	Madrid
27	30	Berlin
28	35	Hong Kong
29	33	Miami
30	20	Milan
31	24	Toronto
32	25	Montreal
33	43	Tel Aviv
34	29	Istanbul
35	32	Lisbon
36	39	Athens
37	27	Nicosia
38	17	Sydney
39	-	Doha
40	47	Ljubljana
41	67	Shanghai
42	42	São Paulo
43	31	Seoul
44	51	Riga
45	36	Auckland
46	49	Taipei
47	52	Manama
48	41	Rio de Janeiro
49	54	Bratislava
50	61	Bangkok
51	50	Prague
52	65	Beijing
53	45	Tallinn
54	59	Vilnius
55	44	Warsaw
56	37	Moscow
57	46	Budapest
58	55	Sofia
59	60	Kiev
60	69	Lima
61	70	Buenos Aires
62	48	Santiago
63	62	Nairobi
64	64	Johannesburg
65	63	Jakarta
66	57	Bogotá
67	53	Bucharest
68	58	Mexico City
69	-	Cairo
70	71	Kuala Lumpur
71	66	Manila
72	68	Delhi
73	56	Mumbai

• Mercer's rank:

2009    2008    Cities

1	2	Tokyo
2	11	Osaka
3	1	Moscow
4	8	Geneva
5	6	Hong Kong
6	9	Zurich
7	7	Copenhagen
8	22	New York City
9	20	Beijing
10	13	Singapore
11	10	Milan
12	24	Shangai
13	12	Paris
14	4	Oslo
15	89	Caracas
16	3	London
17	14	Tel Aviv
18	16	Rome
19	21	Helsinki
20	52	Dubai
21	19	Vienna
22	61	Shenzhen
23	55	Los Angeles
23	70	Guangzhou
25	16	Dublin
26	65	Abu Dhabi
27	34	Douala
28	25	Athens
29	25	Amsterdam
30	45	Bratislava
31	89	White Plains
32	30	Lagos
33	74	Tehran
34	51	Abidjan
34	41	Dakar
34	78	San Francisco
37	28	Madrid
38	43	Luxembourg
38	31	Barcelona
40	57	Algiers
41	77	Honolulu
41	39	Brussels
41	80	Beirut
44	44	Almaty
45	75	Miami
46	18	St Petersbourg
47	37	Munich
48	40	Frankfurt
49	38	Berlin
50	84	Chicago