Table:
proximal determinants - physical environments and resources
at least one chronic condition
fair or poor self-rated general health
fair or poor self-rated mental health

less than high school education
0.66
0.26
0.15

high school education or higher
0.61
0.21
0.13

unemployed
0.61
0.25
0.17

employed
0.60
0.15
0.10

annual household income in lowest tercile
0.64
0.26
0.16

annual household income above lowest tercile
0.62
0.20
0.12

food insecure
0.71
0.28
0.19

food secure
0.61
0.20
0.12

A merged cell in a table can be described using the JSON {'top-left':(x, y), 'bottom-right':(z, w)}. Here, '(x, y)' represents the top-left and '(z, w)' the bottom-right cells' (row_id, column_id) of the merged region. Using the displayed table image, identify all such merged cells in this table and report their locations in the given format. Note that the numbering of both row and column IDs starts at 1.

This table does not contain any merged cells.