The housing report that the Government had to correct is once again full of errors

PalmThe Balearic government had to revise the report it commissioned on the advisability of limiting rental prices in the Balearic Islands. The study, which cost €15,519.46, contained 101 calculation errors. as reported by ARA BalearesThe Housing Minister, José Luis Mateo, asserted that the authors themselves had corrected the "errors" in the percentages and insisted that, in any case, they did not affect the report's conclusions, which advise against (and support the Government's position on) limiting rental prices. However, the new version of the document again contains errors, one of them precisely in the conclusions section.

In the first version sent to the Ministry, the study—authored by Sergio Nasarre, Professor of Civil Law and founder of the UNESCO Chair, and Santiago Ariste, Professor of Methodology of Analysis at Rovira i Virgili University—contained mistakes in more than half of the tables. The percentages were incorrect in 13 of the 25 tables provided to support the authors' argument, according to calculations by this newspaper, verified with experts. Most of the figures for increases and decreases in the evolution of rented apartments, residential and temporary rental deposits, and the average rental price contained errors. Mateo admitted these mistakes, but nevertheless defended the value of the document, titled Report on the advisability of introducing a rent control system for residential rentals in the Balearic Islands"I would like to make it clear that it not only provides data related to our islands, but also that, with reliable data, it is clear that this solution has not yielded good results in Catalonia," he explained at a press conference. He also insisted that he was "satisfied" with the study.

As explained by Eduard Robsy, an economist specializing in housing and elected PSIB councilor in Menorca, and as verified by ARA Baleares through recalculations, one of the 13 tables containing errors in the percentages has not been updated—specifically, table number 21. It retains the same errors: 14 incorrect percentages. Furthermore, table 25 of the study, which shows "the evolution of the number of residential rental deposits on the four largest islands," displays figures for Ibiza lower than the sum of the Ibiza municipalities listed in the detailed tables: Ibiza Town, San José de la Atalaya, Santa Eulalia del Río, and San Antonio (tables 23 and 24). For example, for the year 2020, the report details 401 residential rental deposits in Ibiza, contradicting its own previous tables, which explained that in that year there were 204 in Ibiza, 102 in San Antonio de Portmany, 83 in San José de la Atalaya, and 80 in Santa. That is, a total of 469.

The same error is repeated throughout the column for the years from 2020 to 2024. The same occurs again in table 28, relating to the number of temporary rental deposits in the four islands, and also with respect to the data for Ibiza, the island that suffers the most. In this case, the figures do not match those in tables 26 and 27 by municipality. Finally, there is another error in the conclusions section. Although the report's authors corrected most of the tables with percentage errors, they did not do the same in this chapter. The text emphasizes that, "between 2020 and 2024, residential security deposits fell sharply in most Balearic municipalities," reaching a decrease of 70% in some cases. However, in the updated tables, the lowest value shown is a 61.8% reduction in Formentera.

Criticisms of the methodology

Beyond the numerous miscalculations and errors, several Experts consulted by ARA Baleares also criticized the study's methodology."It's a pure cherry picking“There is no attempt at projection or real comparison,” Robsy asserts, referring to a concept (translated into Catalan as “cherry selection”) that, in academic and research circles, refers to the manipulation of evidence through the deliberate selection of data that exclusively support a predetermined conclusion. “There is no attempt at projection or real comparison,” he laments: “The trend in new deposits is probably more to blame for the change in contract duration from three to between five and seven years that took place in 2019.”

The 51-page report concludes that rent controls reduce “the availability of rental housing,” intensify “competition,” and create “distributive distortions that unequally affect households with different income levels.” It relies on "international and national literature" and also highlights that when regulations are tightened, "part of the supply migrates towards less regulated modalities." Based on figures from Catalonia, it argues that accompanying measures to expand supply risks exacerbating existing problems.