Concept: For the sake of time series organization, exchange rates have been grouped in two segments: I – Administered or free rates, covering the whole period since 1899, and II – Floating rates, which have been in place in the period of January 1989 to January 1999 and coexisted with the first segment.   I – Administered or free exchange rates   Available since 1899. In this period covered by the time series a great diversity of foreign exchange policies have been adopted. During some times, exchange rates were fixed (i.e. administered) by the monetary authorities, whereas in other times rates were freely agreed by market participants (i.e. they were free) and there were even times when both administered and free rates have existed at the same time. It should also be emphasized that between 1953 and 1961 a system of multiple exchange rates have been in place. For these time series the following kinds of exchange rates have been considered: -          From January 1899 to January 1953 – administered rates; -          From February 1953 to October 1961 – free rates, coming from the Exchange Portfolio of the Banco do Brasil. In this period administered rates have also been in place, with sell rates fixed on: CR$ 18,72, from Feb/1953 to Jul/1953; CR$ 18,82, from Aug/1953 to Dec/1958; and CR$ 18,92, from Jan/1959 to Feb/1961. In the beginning of the period most transactions were channeled through the administered rates system. As time went by, the number of transactions going through the free rates system grew. -          From November 1961 to February 1990 – administered rates; and -          From March 1990 onwards, free rates (Resolution 1.690 from 18.3.1990).   The corresponding time series are the following ones: -          Commercial dollar (sell and buy) – daily rates Available from 28.11.1984 onwards, refers to administered rates up to March 13th 1990 and to free rates from this date on (Resolution 1.690 from 18.3.1990). Administered rates are the ones fixed by the Central Bank. Free rates are the average of the rates of transactions effectively closed in the interbank market, weighted by the volume of sell transactions in the day. Outliers and rates presenting evidence of manipulation or other violations of the generally accepted market practices are excluded from the calculation. From March 1992 on, this rate was named PTAX. The series “American dollar – buy and sell – end of period” and “American dollar – buy and sell – period average” are derived respectively from these buy and sell daily rates.   -          American dollar – end of period Refers to the dollar administered rates expressed in Mil-réis for the period 1899-1941. The Mil-réis/dollar rates for the period 1899-1921 were computed from the pound/dollar parity. Discontinued in 1941.   -          American dollar (buy and sell) – end of period Annual rates are available from 1942 on and monthly rates from January 1953 on. End of period values correspond to the daily rate of the reference period´s last day.   -          American dollar (buy and sell) – period average Annual rates are available from 1942 on and monthly rates from January 1953 on. Buy and sell average rates are computed from the reference period daily rates. Monthly and annual rates were computed based on the running days of the reference up until December 1973. From January 1974 on, rates were weighted by the working days.   II – Floating exchange rates   Created by the Resolution 1.552 from 22.12.1988, this segment of the exchange market allowed markets participants to freely agree on the price of the foreign currency being negotiated. It initially covered only transactions related to international travel motivated by tourism, business, education and health. Later, other kinds of transactions were incorporated in the segment, such as gold, Brazilian investments abroad, unilateral transfers and some services. On 31.1.1999 this segment was terminated and the free and floating rates were merged. Series related to this segment are the following:   -          Tourism dollar (sell) Daily rates in the floating rate segment, available for the period between 27.5.1993 to 29.1.1999. The computation of this rate takes into account transactions in the interbank market weighted by the volume of sell transactions. Outliers and rates presenting evidence of manipulation or other violations of the generally accepted market practices are excluded from the computation. The series “American dollar – buy and sell – end of period” and “American dollar – buy and sell – period average” are derived respectively from these buy and sell daily rates.   -          American dollar (buy and sell) – end of period Rates for the last day of the reference period, computed for both buy and sell transactions.   -          American dollar (buy and sell) – period average Average of the daily rates of the reference period (month or year), computed for buy and sell transactions, weighted by the number of working days.

Source: Central Bank Information System – PTAX800 transaction