How often were tax assessments reevaluated under Diocletian’s fiscal system?

Under Diocletian’s fiscal system, tax assessments were initially made every five years. This system was later consolidated into a 15-year cycle known as an indictio (or indiction), a practice that began in 312 CE.123

While the government established the rate of tax per fiscal unit annually, the underlying census and reassessment of taxable resources occurred according to this 15-year cycle. This reform was part of the jugatio-capitatio system, which calculated land taxes based on the extent and quality of land, types of crops, and the number of settlers and cattle.3