The table of Contribution Bases reflects, month by month, the amount of the contribution bases registered by the people selected in the MCVL throughout their working life. Both the bases corresponding to employment and those corresponding to self-employed activity and other special contribution situations are included.

The table of People includes a row or record for each natural person selected for the Sample, collecting in columns their essential demographic characteristics that appear in the databases of the Social Security and the Municipal Register.

The column structure of this table is the same in both versions of the MCVL (with or without tax data), but there are some differences in the format of the natural person identifier (IPF). In addition, in the case of the version of the MCVL with tax data, there may be more than one row or record for the same IPF, due to the identification process of said Agency.

The Affiliation table shows the essential data of the episodes of affiliation to Social Security that the person selected for the MCVL has maintained throughout his life.

In general, the table will show a record for each episode of affiliation, understood as a period of time that elapses between a date of registration and a date of withdrawal, both included, during which the worker, either through an employer or an entity identified by his contribution account code, or as a self-employed worker,  remains in a situation of registration in Social Security, which, generally, will imply the obligation to contribute. The table shows episodes of affiliation that will reflect both situations of high employment, which are the most frequent, as well as high unemployment, registration in special agreement, etc.

The pension table shows the fundamental characteristics of the pensions received, or have received in the past, by the people included in the sample, such as the type of pension (disability, retirement, widowhood, etc.), the date on which it was recognized and the amount of the different payment concepts that are integrated into it.

Most of the people selected for the MCVL have never received a Social Security pension. Records only appear in the pension table for those people included in the MCVL who receive or have ever received them.

The table of Cohabitants includes a row or record for each natural person selected for the MCVL that is registered in the Continuous Municipal Register, so that the registration sheet in which it is registered can be identified. 96.5% of the people selected for the sample are also included in the Register. In each row or record of the table appear the date of birth and sex of both the person included in the sample and the other people (cohabitants), if any, who are registered on the same registration sheet

The Tax Data table contains individualized information on the perceptions (salaries, remuneration, pensions, etc.) paid to the people included in the MCVL during the reference year, as well as some data related to their family situation when they are necessary for the application of tax reductions or benefits. This information comes from form 190 (annual summary of withholdings and income on account of Personal Income Tax) of the State Agency of the Tax Administration.

The Tax Data table is incorporated into the MCVL only in the version called, in short, MCVL CDF (or also MCVLT). This version is prepared by the State Agency of the Tax Administration and is published annually, with some delay compared to the version without tax data. The MCVL CDF or MCVLT is only available from the 2006 edition.