(see French colonization of the Americas). By the middle of the 16th century, France's demographic growth, its increased demand for consumer goods, and its rapid influx of gold and silver from Africa and the Americas led to inflation (grain became five times as expensive from 1520 to 1600), and wage stagnation. Although many land-owning peasants and enterprising merchants had been able to grow rich during the boom, the standard of living fell greatly for rural peasants, who were forced to deal with bad harvests at the same time. This led to reduced purchasing power and a decline in manufacturing. The monetary crisis led France to abandon (in 1577) the livre as its money of account, in favor of the écu in circulation, and banning most foreign currencies. Meanwhile, France's military ventures in Italy and (later) disastrous civil wars demanded huge sums of cash, which were raised with through the taille and other taxes. The taille, which was levied mainly on the peasantry, increased from 2.5 million livres in 1515 to 6 million after 1551, and by 1589 the taille had reached a record 21 million livres. Financial crises hit the royal household repeatedly, and so in 1523, Francis I established a government bond system in Paris, the "rentes sure l'Hôtel de Ville". The French Wars of Religion were concurrent with crop failures and epidemics. The belligerents also practiced massive "scorched earth" strategies to rob their enemies of foodstuffs. Brigands and leagues of self-defense flourished; transport of goods ceased; villagers fled to the woods and abandoned their lands; towns were set on fire. The south was particularly affected: Auvergne, Lyon, Burgundy, Languedoc—agricultural production in those areas fell roughly 40%. The great banking houses left Lyon: from 75 Italian houses in 1568, there remained only 21 in 1597. Rural society In the 17th century rich peasants who had ties to the market economy provided much of the capital investment necessary for agricultural growth, and frequently moved from village to village (or town). Geographic mobility, directly tied to the market and the need for investment capital, was the main path to social mobility. The "stable" core of French society, town guildspeople and village laborers, included cases of staggering social and geographic continuity, but even this core required regular renewal. Accepting the existence of these two societies, the constant tension between them, and extensive geographic and social mobility tied to a market economy holds