Recruits in the early 18th century had to be physically and mentally fit, between 18 and 36 years old (18–30 years from 1819, 18–25 years from 1871) and at least 172 centimeters tall (175 cm from 1775, lowered to 167 cm from 1788 as the army was in dire need of soldiers during Gustav III's Russian War). Many soldiers served in the army for more than 30 years, as there was no service time stated in the contract; instead, being discharged required a reason, such as old age, injury, sickness, or the commission of a crime. Discharges were generally only given at general musters, held once a year, or even more sparsely, even though an interim discharge could be given by the regimental commander if the discharge was supported by the soldier. The interim discharge had to be confirmed at the next general muster.