Patterson-UTI Energy, Inc. reported drilling activity for the month and three months ended December 31, 2018. For the month, the company had an average of 185 drilling rigs operating. For the three months ended December 31, 2018, the Company had an average of 183 drilling rigs operating. Average drilling rigs operating reported in the Company's monthly announcements represent the average number of the Company's drilling rigs that were operating under a drilling contract. The Company cautioned that numerous factors in addition to average drilling rigs operating can impact the Company's operating results and that a particular trend in the number of drilling rigs operating may or may not indicate a trend in or be indicative of the Company's financial performance. The Company intends to continue providing monthly updates on drilling rigs operating shortly after the end of each month.