performance of imputation for experiments a and b
Table:
experiment, and length of gap in years
number of postal codes erased and imputed
percentage of postal codes erased and imputed
rule a applied
rule b applied
perfect matches

number
percent

experiment a

1
1,572,760
90.6
91.6
8.4
77.0

2
151,305
8.7
91.5
8.5
72.1

3
10,815
0.6
75.9
24.1
56.5

4
720
0.0
76.7
23.3
51.7

5
20
0.0
60.0
40.0
35.0

total - experiment a
1,735,620
100.0
91.5
8.5
76.4

experiment b

1
2,830,755
81.6
91.4
8.6
76.8

2
547,870
15.8
91.4
8.6
72.0

3
78,510
2.3
76.1
23.9
56.8

4
10,050
0.3
76.2
23.8
53.5

5
1,090
0.0
58.2
41.8
38.0

6
115
0.0
59.6
40.3
29.8

7
15
0.0
64.3
35.7
35.7

total - experiment b
3,468,405
100.0
91.0
9.0
75.5

Give a concise answer to this question supported by the table contents. Use the JSON format {"answer": ["YOUR ANSWER"]}. When several items apply, list them comma-separated. The table is captioned 'performance of imputation for experiments a and b'. Now answer the following question based on the table information: How many total gaps were created in experiment b?

{"answer": ["3468405"]}