Table:
net profits per employee

high-growth enterprises
moderate-growth enterprises
low-growth enterprises
young enterprises in a well-established market
experienced enterprises in a well-established market
young enterprises in an emerging market
experienced enterprises in an emerging market
full sample

ordinary least square regressions

mp_index
-1.040 (0.433
0.926 (0.841
1.388 (0.495
1.056 (0.507
1.514 (0.476
-0.990 (1.182
-0.514 (0.614
0.878 (0.441

strat_lt_index
0.204 (0.815
-1.349 (0.827
0.149 (0.700
-0.165 (0.984
-0.927 (0.617
0.142 (1.096
0.657 (0.694
-0.020 (0.601

r2
0.497
0.269
0.290
0.716
0.311
0.531
0.198
0.197

number of enterprises
241
743
1,244
190
1,234
102
702
2,228

Examine the table in this image and extract any merged cell regions. Please format the merged cell regions as JSON {'top-left':(x, y), 'bottom-right':(z, w)}, with (x, y) indicating the (row_id, column_id) of the top-left cell and (z, w) the bottom-right cell in the merged regions. Remember that the x, y, z, w all start from 1.

The merged cell regions are as follows:
{'top-left':(1, 1), 'bottom-right':(3, 1)}
{'top-left':(1, 2), 'bottom-right':(1, 9)}
{'top-left':(3, 2), 'bottom-right':(3, 9)}.