On Friday's broadcast of CNBC's "Squawk on the Street," Cleveland Federal Reserve Bank President Loretta Mester stated that the latest Personal Consumption Expenditures (PCE) price index shows that progress on inflation "has been slow and in fits and starts" and "we just haven't been making very strong progress on inflation" "and it's concerning." And that forward-looking data "also suggests that price pressures remain pretty darn high and pretty stubborn."