What is an acceptable audit deficiency rate?

Audits were reported for three of the four "Big 4" firms. "The 28 deficient audits the Public Company Accounting Oversight Board found in its 2013 inspection of the firm were out of 57 audits or partial audits conducted by Ernst & Young that the PCAOB evaluated—a deficiency rate of 49%. In the previous year, the board's inspectors found deficiencies in 25 of 52 audits inspected, a rate of 48%." (WSJ, 8/28/2014, Ernst & Young 2013 Audit Deficiency Rate 49%, Regulators Say) "The 19 deficient audits were out of 59 PwC audits and partial audits reviewed by the Public Company Accounting Oversight Board in its annual inspection report on the firm issued Monday. That rate of 32% is down from last year's 39%, when the PCAOB found 21 deficient audits out of 54 inspected." (WSJ, 6/30/2014, Inspection Finds Defects in 19 PricewaterhouseCoopers Audits) "The findings, issued Monday, were a slight uptick from the rate of problems the regulator found at Deloitte in last year's inspection. The 15 deficient audits represented 28% of the 53 Deloitte audits and partial audits reviewed by the Public Company Accounting Oversight Board in its 2013 inspection report on the firm." (WSJ, 6/2/2014, Regulator Finds Deficiencies in 15 Deloitte & Touche Audits) Will identifying the lead audit partner improve these results? The rule should be ready this month.