According to a representative survey conducted in 1974, over 40% of mothers did not breastfeed, 25% breastfed for up to four weeks, and less than 10% for up to eight weeks. Perhaps the perception has shifted somewhat in favor of breastfeeding since then, but it certainly does not look significantly different. As late as 1964, more than 80% of mothers were breastfeeding, with over 40% doing so without supplemental feeding. Even earlier, breastfeeding was considered a matter of course. In the oldest Latin writings in Germany that deal with infant nutrition, breast milk is described as the only possible food; however, it was suggested that expressed milk be mixed with a bit of wine. If illness makes breastfeeding inadvisable, bread, thin beer, and honey or sugar should be used instead of breast milk. There are also varying accounts regarding the duration of breastfeeding. In 1765, a 12-month breastfeeding period was considered natural.