number of Sammarinese euro coins, as was the case with the lira before it, are primarily of interest to coin collectors. San Marino's per capita GDP and standard of living are comparable to that of Italy. Key industries include banking, electronics, and ceramics. The main agricultural products are wine and cheese. San Marino imports mainly staple goods from Italy. San Marino's postage stamps, which are valid for mail posted in the country, are mostly sold to philatelists and are a significant source of income. San Marino is no longer a member of the Small European Postal Administration Cooperation. It has the world's highest rate of car ownership, being one of two countries with more vehicles than people, alongside Andorra. Taxation The corporate profits tax rate in San Marino is 17%, capital gains are subject to a five percent tax, and active interest is subject to an 11% withholding tax. Several benefits apply to new businesses, which can strongly reduce the amount of taxes to be paid. The personal income tax (IGR, ) was introduced in 1984 and it was heavily reformed in 2013 with the goal of increasing fiscal revenue. The nominal tax rate ranges from 9% for an annual revenue below €10,000 to 35% for revenues above €80,000. In 1972, a value-added tax (VAT) system was introduced in Italy, and an equivalent tax was introduced also in San Marino, in accordance with the 1939 friendship treaty. However, this tax is not a standard value-added tax, but rather it is an import tax, thus, it is levied only on imported goods and raw resources. For this reason it is locally best known as single stage tax (), as it is only applied one time during importation, while VAT is applied at every exchange. Furthermore, while VAT also applies to services, the import tax only applies on physical goods. Another important difference is that while VAT is computed on the final price paid by the consumer, the import tax is levied on the importation cost paid by the company, which is generally much lower. Under the European Union customs agreement, San Marino import tax is considered equivalent to the European VAT system. A separate tax on services, with a rate of 3%, has been introduced in 2011. The introduction of a true VAT system, not dissimilar from the European one, is under development. Because San Marino's tax rate is lower than