Encuesta de Fecundidad
Characteristics marriages / couples and exposure to pregnancy risk. Women  15-49 years
Average duration 1st relation, single females with some relation,level of studies and age actual (years).
Unidades: Average duration (years)

;Total;From 15 to 19 years old;From 20 to 24 years old;From 25 to 29 years old;From 30 to 34 years old;From 35 to 39 years old;From 40 to 44 years old;From 45 to 49 years old;
Total;0,9;0,1;0,2;0,9;2,4;5,4;3,6;3;
Illiterate;8,1;..;4;6,7;13;11;20;0;
Without studies;5,9;4;..;0;15;6,7;0;0;
Primary education and second grade, GBE or first year of GCSE;1,5;0,2;0,5;1,5;3,1;8,3;4,2;5,1;
Secondary Education and Post-secondary non-higher;0,5;0;0,1;0,6;2,3;6,3;2,6;0;
1º, 2º and intermediate technical-professional studies;0,6;0,1;0,1;1;2,3;1,9;7,6;0;
Higher level technical-professional studies;0,9;0;0,2;1,5;2;0;0;0;
First year of tertiary education;0,8;0;0;0,8;1,5;0;2,4;6,1;
Tertiary education, university graduates and doctors;0,5;..;0;0,1;1,7;2;1,9;0,6;
Notas:
Fuente: National Statistics Institute