Table:
Year

Sunday Times
Rich List

Forbes
The World's Billionaires

Rank

Net worth
(£) bn

Rank

Net worth
(US$) bn

2005

3

$25.00

2006

1

£14.88

5

$23.50

2007[50]

1

£19.25

5

$32.00

2008[48][49]

1

£27.70

4

$45.00

2009[51][52]

1

£10.80

8

$19.30

2010[53][54][55]

1

£22.45

5

$28.70

2011[56][57]

1

£17.50

6

$31.10

2012[58]

1

£12.70

21

$20.70

2013[59][60][61]

4

£10.00

41

$16.50

2014[62][63]

3

£10.25

52

$13.70

2015[12][64][65]

7

£9.20

82

$13.50

2016[45][47]

11

£7.12

135

$8.40

Given a table image, please tell me which table cells are merged cells. Return the merged cell regions in the JSON format of {'top-left':(x, y), 'bottom-right':(z, w)}, where (x, y) and (z, w) represent the (row_id, column_id) coordinates of top-left cell and bottom-right cell, respectively. The row_id and column_id are numberd from 1.

The merged cell regions are as follows:
{'top-left':(1, 1), 'bottom-right':(2, 1)}
{'top-left':(1, 2), 'bottom-right':(1, 3)}
{'top-left':(1, 4), 'bottom-right':(1, 5)}.