Level of studies	Duration of open interval between births (months)	Total
Total	Total	100
Total	From 0 to 7 months	23,24
Total	From 8 to 11 months	1,79
Total	From 12 to 23 months	6,62
Total	From 24 to 35 months	6,01
Total	From 36 to 47 months	5,26
Total	From 48 to 59 months	4,07
Total	60 and over	53
Illiterate	Total	100
Illiterate	From 0 to 7 months	13,47
Illiterate	From 8 to 11 months	3,98
Illiterate	From 12 to 23 months	7,92
Illiterate	From 24 to 35 months	4,35
Illiterate	From 36 to 47 months	1,12
Illiterate	From 48 to 59 months	..
Illiterate	60 and over	69,15
Without studies	Total	100
Without studies	From 0 to 7 months	22,83
Without studies	From 8 to 11 months	0,49
Without studies	From 12 to 23 months	2,17
Without studies	From 24 to 35 months	0,83
Without studies	From 36 to 47 months	2,52
Without studies	From 48 to 59 months	1,6
Without studies	60 and over	69,55
Primary education and second grade, GBE or first year of GCSE	Total	100
Primary education and second grade, GBE or first year of GCSE	From 0 to 7 months	23,92
Primary education and second grade, GBE or first year of GCSE	From 8 to 11 months	1,14
Primary education and second grade, GBE or first year of GCSE	From 12 to 23 months	5,24
Primary education and second grade, GBE or first year of GCSE	From 24 to 35 months	5,03
Primary education and second grade, GBE or first year of GCSE	From 36 to 47 months	4,88
Primary education and second grade, GBE or first year of GCSE	From 48 to 59 months	2,5
Primary education and second grade, GBE or first year of GCSE	60 and over	57,29
Secondary Education and Post-secondary non-higher	Total	100
Secondary Education and Post-secondary non-higher	From 0 to 7 months	16,44
Secondary Education and Post-secondary non-higher	From 8 to 11 months	1,97
Secondary Education and Post-secondary non-higher	From 12 to 23 months	9,2
Secondary Education and Post-secondary non-higher	From 24 to 35 months	8,13
Secondary Education and Post-secondary non-higher	From 36 to 47 months	5,42
Secondary Education and Post-secondary non-higher	From 48 to 59 months	5,35
Secondary Education and Post-secondary non-higher	60 and over	53,48
1º, 2º and intermediate technical-professional studies	Total	100
1º, 2º and intermediate technical-professional studies	From 0 to 7 months	27,3
1º, 2º and intermediate technical-professional studies	From 8 to 11 months	2,75
1º, 2º and intermediate technical-professional studies	From 12 to 23 months	7,71
1º, 2º and intermediate technical-professional studies	From 24 to 35 months	7,38
1º, 2º and intermediate technical-professional studies	From 36 to 47 months	7,13
1º, 2º and intermediate technical-professional studies	From 48 to 59 months	8,06
1º, 2º and intermediate technical-professional studies	60 and over	39,67
Higher level technical-professional studies	Total	100
Higher level technical-professional studies	From 0 to 7 months	13,98
Higher level technical-professional studies	From 8 to 11 months	..
Higher level technical-professional studies	From 12 to 23 months	23,02
Higher level technical-professional studies	From 24 to 35 months	..
Higher level technical-professional studies	From 36 to 47 months	37,7
Higher level technical-professional studies	From 48 to 59 months	..
Higher level technical-professional studies	60 and over	25,3
First year of tertiary education	Total	100
First year of tertiary education	From 0 to 7 months	24,07
First year of tertiary education	From 8 to 11 months	2,79
First year of tertiary education	From 12 to 23 months	6,75
First year of tertiary education	From 24 to 35 months	8,2
First year of tertiary education	From 36 to 47 months	3,51
First year of tertiary education	From 48 to 59 months	4,64
First year of tertiary education	60 and over	50,03
Tertiary education, university graduates and doctors	Total	100
Tertiary education, university graduates and doctors	From 0 to 7 months	21,49
Tertiary education, university graduates and doctors	From 8 to 11 months	4,41
Tertiary education, university graduates and doctors	From 12 to 23 months	12,15
Tertiary education, university graduates and doctors	From 24 to 35 months	7,8
Tertiary education, university graduates and doctors	From 36 to 47 months	6,01
Tertiary education, university graduates and doctors	From 48 to 59 months	6,99
Tertiary education, university graduates and doctors	60 and over	41,14