The probability of freedom from PWN by 2018 for two initial prior probabilities of freedom. The solid lines indicate the median of the assessment results when the initial prior probability of freedom was equal to 0.5 and the dashed lines indicate the results when the initial prior probability of freedom was equal to 0.25. Red denotes the import-export surveys and blue denotes the early detection surveys. Only one red line is visible, as the two lines overlap.