An online stock trading company makes part of their revenue from clients when the clients trade stocks therefore, it is important to the company to have an good idea of how many trades its clients are making in a given year. In a sample of 86 clients of an online stock trading company, the average number of trades per year was 81 with a standard deviation of 19. If you were to test the hypothesis that the average number of trades per year is different than the previous year when the average number of trades was 86 (using the 10% level of significance), what is the critical value? (please round your answer to 2 decimal places)