Challenges to Property Tax Administration in Porto Alegre, Brazil
The property tax in Brazil is an annual tax on urban land and buildings administered at the local government level. The tax base is derived from market value and is standardized across different local authorities, although procedures for establishing the tax base and rates vary considerably.
In the city of Porto Alegre, the cost approach is the method traditionally employed for assessing real estate property for taxation purposes. No legal requirement exists concerning intervals between valuations, and the last general valuation took place in 1991. In years without valuations, the tax base has been readjusted uniformly according to prevailing inflation rates. The property tax rates are progressive, with sliding rates for six classes of assessed values to insert an element of "ability-to-pay" into the system. The tax is calculated by the sum of each portion of the assessed value multiplied by the respective rate for that class. The maximum rate for residential property reaches 1.2 percent.
Analysis of the Current System
A recent analysis of the property tax system in Porto Alegre sought to provide a full examination of the relationship between assessed values and sale prices. Some of the results are summarized below.
Assessment level and uniformity
Residential apartments in Porto Alegre were assessed on median at only 34 percent of their sale prices, much less than the statutory level of 100 percent. Using the coefficient of dispersion about the median [COD] of the assessed value to sale price ratio as a measure of variability, the results showed a low degree of assessment uniformity (approximately 36 percent). In Brazil, there are neither local nor national standards for evaluating assessment performance. By comparison, a commonly accepted degree of uniformity for single-family residential property in the United States is a coefficient between 10 and 15 percent. Figure 1 illustrates the ample spread of the assessment ratios in this study.
Factors determining assessment inequity
To examine the simultaneous effects of the factors determining assessment bias, a multivariate model was used to investigate both vertical and horizontal inequities. The model detected a large number of factors causing systematic differences in assessment levels, including location attributes, building quality, building year, presence of elevators and similar variables. Vertical assessment regressivity was also identified.
Assessment method
It is plausible to assert that the method traditionally employed for assessing real property, that is, the cost approach, is a major cause of the lack of assessment uniformity identified in this study. Some theoretical weaknesses of the approach are associated with the extensive number of simplifications implemented by the local authority to make its application easier, and these adjustments are likely to have determined assessment bias. Inconsistencies with the standard cost model include the lack of connection between cost tables and the performance of the real estate market, and low correlation between the ad hoc depreciation rates adopted and the reduction in price caused by age, obsolescence, or deterioration of building structures. Furthermore, lack of systematic control over valuation performance seems to have contributed to the high inaccuracy of assessed values.
Time lags between valuations
The method used to make an overall adjustment to assessed values based on prevailing inflation rates for years without valuation has clearly contributed to the reduction of the tax base. For instance, properties were assessed on median at 38 percent of their sale prices in 1993, but only 27 percent in 1995.
Effective versus statutory rates of property tax
Rates for residential property are progressive according to six classes of assessed value. The effective rate results from the actual amount raised from property taxation, without regard to tax evasion, divided by the sale price. The statutory rate results from the expected tax that could be raised per property, if the tax were established on the basis of sale price, divided by its sale price. The effective rate is much lower than the statutory rate and represents on median only 0.17 percent of sale price.
Improper assessment practices have affected the distribution of the tax burden, not only because assessed values do not bear a consistent relationship to sale prices but also because many properties are classified incorrectly. The actual property tax revenue collected in the period under study represented approximately 25 percent of the potential revenue to be raised if assessed values were equal to sale prices.
Causes of Poor Property Tax Administration
Historical factors may help to explain the current poor administration of the property tax in Porto Alegre and its inefficient use as a revenue source. During the 1970s, large transfers of revenue from the central government and private estates to municipalities complemented the revenue raised at the local government level. Consequently, local authorities were not interested in collecting their own taxes, and taxpayers were used to paying insignificant property tax bills. The achievement of good performance in terms of valuation and an acceptable degree of assessment equity were secondary issues.
Recent financial crises combined with the urgent need for public investment in infrastructure equipment and services have stimulated some local authorities to improve their tax systems. However, due to the high visibility of the property tax and taxpayer antipathy, efforts to recover revenue and achieve assessment equity often result in tax revolts. Furthermore, changes in the tax base must be approved by locally elected members of the Chamber of Councilors. Whenever general valuations are planned, the Council members are responsible for supporting capping systems in the name of protecting the poor and retired taxpayers. However, the capping systems actually favor high-income and wealthy taxpayers because low-income and retired taxpayers can receive relief based on their income.
Since 1991, two proposals for altering the property tax base in Porto Alegre have been rejected by the Chamber of Councilors because the estimated value of some properties would have been adjusted over the inflation rate at the time. However, the existing vertical assessment inequity means that high-valued properties are the ones benefiting from poor property tax administration.
Recommendations on Revising Practices and Attitudes
Knowledge about the weaknesses of a particular tax system is fundamental for its improvement, and the analysis undertaken in Porto Alegre provides greater understanding of the current system, the degree of assessment inequity and its main causes. For the first time, the drawbacks and weaknesses of the system are both quantified and measured, including which properties are benefiting from the system and the amount of revenue being lost. Now Porto Alegre has the opportunity to improve its property tax system on the basis of accurate data rather than political expediency.
Several measures would contribute to the overall equity of the tax system while also improving revenue collection to provide the community with higher standards of living:
§ Reassessment of properties based on current market values using the sales comparison approach to assessing residential property, such as multiple regression analysis (MRA), artificial neural networks (NN), or multilevel modeling (hierarchical linear models - HLMs).
§ Systematic control over assessed property values, including testing before the release of the valuation roll to recognize and adjust for eventual bias in the estimated tax base.
§ Assurance of regular assessment updates.
§ Establishment of market adjustments to assessed values based on ratio studies for years without valuation.
§ Transparency in the administration of the property tax, especially in graduating the size of the tax burden, instead of overriding estimates of market values arbitrarily for this purpose.
§ A definition of minimum standards for assessment performance at the local or national level.
The achievement of property tax equity and the provision of a high standard of public services are common goals for politicians, the community, administrators and others. Public officials need to take advantage of new technologies for property tax assessment and data gathering to make tax systems operate both efficiently and fairly. However, technical improvements are just a part of the process. It is also vital to work on public opinion. An important step is to encourage dialogue between community residents and politicians, showing the drawbacks of the current system and the consequences of keeping its structure. Confidence in the property tax system is likely to increase if revisions are discussed seriously in the public domain.
Claudia M. De Cesare is an assessor in the Department of Local Taxation for the Municipality of Porto Alegre. She received a Lincoln Institute Dissertation Fellowship in 1999 to support the research reported here and in her Ph.D. thesis, which she completed at the University of Salford in England. The Lincoln Institute is continuing to develop educational programs with administrators, politicians, scholars and the community in Porto Alegre to help improve the equity and efficiency of the property tax system.