The economy of the Empire of Brazil was centered on export of raw materials when the country became independent in 1822. The domestic market was small, due to lack of credit and the almost complete self-sustainability of the cities, villages and farms that dedicated themselves to food production and cattle herding. During the first half of the 19th century, the Imperial Government invested heavily in the improvement of roads while retaining an excellent system of ports. The former facilitated better commercial exchange and communication between the country's distant regions; the latter did the same for foreign trade. The Brazilian economy was extremely diversified in the post-Independence period, but a great effort was required of the monarchical government to carry through the change from a purely colonial economic system based on slavery to a modern capitalist system. Until its end, the monarchy continued the notable economic growth that began with the arrival of Prince Regent Dom João in 1808. This was caused, in part, by the liberalism adopted by successive Government cabinets up to 1889 that favored the private initiative. Economy Currency The unit of currency under the Empire (and until 1942) was the real ("royal"), plural réis, a name derived from the Portuguese real. It was usually called milréis (English: thousand royals), being written as 1$000. "A thousand milréis (1:000$000) was known as conto de réis." One conto de réis was represented by the symbol Rs written before the value and by a dollar sign separating the units group (lower than 1,000 réis). Thus, 350 réis was written as "Rs 350"; 1,712 réis as "Rs 1$712"; and 1,020,800 réis was written as "Rs 1:020$800". This means that the colon functioned as the millions comma and the $ sign as the thousands comma; the colon is the actual group separator, and the $ sign is used only for separating the smaller group of units. Overview For a country devoid of capital, economic improvement would require as much investment as possible in production for export. However, such a course was complicated by the almost complete lack of Brazilian manufactured products. This lack resulted in a considerable increase in importation, creating a continuous deficit. Most prominent among the imports were woven goods, wines, soaps, comestibles, and perfumes, amongst others. Until the 1850s, such items as coal, machinery, cement, iron, iron goods and iron tools represented 11% of the Brazilian imports from Great Britain.