Conferencia impartida por la Dra. Renata Herrerias & Guillermo Zamarripa.

The success of the SAR (Mexican Savings Retirement System) relies on coverage and the amount of savings in workers individual accounts. Meanwhile, the amount on savings depends on the size of the contribution and the time that workers spend in formal jobs, or the density of contribution. We explore who will be entitled to the minimum guaranteed pension, understanding the determinants of the density of contribution. We also establish the key differences among groups of workers affiliated to the SAR based on the type of affiliation and gender. We use a database of contributions and salary trajectory of 40,000 workers across 15 years from 1997 to 2011. With this data we are able to determine the number of times a worker enter or leave the system, the length of stay, length of time without contributions, and the density of contribution. Our results show that there are significant differences between assigned and registered workers. Assigned workers, those who do not select a pension manager, only contribute to their account for one year or less and most of them enter the system once and never come back. The average density of contribution is 16 percent for assigned workers and 55 percent for registered workers. Both groups present a strong positive relation between salaries and density of contribution, i.e. workers with higher salaries tend to contribute more time to their pension. Changes of pension managers, number of employers and whether the worker is male are also positively related to density of contribution. Additionally, workers with housing credit consistently present much higher density of contribution rates. In general, assigned workers are at the bottom of the distribution of density of contribution and most likely they will be excluded from the benefits of the system.