The US economy has overthrown all other economies since then and is ever-growing with the passage of time. A brief chart is given below for further understanding.
Table 1: RAILROAD MILEAGE INCREASE BY GROUPS OF STATES 1850 1860 1870 1880 1890 New England 2,507 3,660 4,494 5,982 6,831 Middle States 3,202 6,705 10,964 15,872 21,536 Southern States 2,036 8,838 11,192 14,778 29,209 Western States and Territories 1,276 11,400 24,587 52,589 62,394 Pacific States and Territories 23 1,677 4,080 9,804 TOTAL USA 9,021 30,626 52,914 93,301 129,774 SOURCE: Chauncey M. Depew (ed.), One Hundred Years of American Commerce 1795-1895 p 111 (Source Wikipedia)
The independent yeoman farmer continued to exist, particularly in New England and the middle colonies, but most settled land in North America by 1750 was devoted to the cultivation of a cash crop. New England turned its land over to the raising of meat products for export. The middle colonies were the principal producers of grains. By 1700 Philadelphia exported more than 350,000 bushels of wheat and more than 18,000 tons of flour annually. The Southern colonies were, of course, even more closely tied to the cash crop system. South Carolina, aided by British incentives, turned to the production of rice and indigo. North Carolina, although less oriented toward the market economy than South Carolina, was nevertheless one of the principal suppliers of naval stores. Virginia and Maryland steadily increased their economic dependence on tobacco and on the London merchants who purchased that tobacco; and for the most part they ignored those who recommended that they diversify their economies by turning part of their land over to the cultivation of wheat. Their near-total dependence upon the world tobacco price would ultimately prove disastrous, but for most of the 18th century Virginia and Maryland soil remained productive enough to make a single-crop system reasonably useful.
As America evolved from subsistence to commercial agriculture, an influential commercial class increased its power in nearly every colony. Boston was the centre of the merchant elite of New England, who not only dominated economic life but also wielded social and political power as well.. And it is clear that the commercial importance of the colonies was increasing. During the years 1700-10, approximately 265,000 sterling was exported annually to Great Britain from the colonies, with roughly the same amount being imported by the Americans from Great Britain. By the decade 1760-70, that figure had risen to more than 1,000,000 sterling of goods exported annually to Great Britain and 1,760,000 annually imported from Great Britain. (Source Britannica encyclopedia)
Situation now days
The United States of America holds the honor of world's greatest economic power in terms of gross national product (GNP) and is among the greatest powers in terms of GNP per capita. The nation's wealth is partly a reflection of its rich natural resources. With only 5 percent of the world's population, the United States produces nearly one-fifth of the world's output of coal, copper, and crude petroleum. The agricultural sector produces nearly one-half of the world's corn (maize); nearly one-fifth of its beef, pork, mutton, and lamb; and more than one-tenth of its wheat.