Figure CNF5.2 shows the average numeracy scores of this group and of grade five students in Papua New Guinea in previous PILNA cycles. The score for these students in 2021 (529.46) was lower than in the 2018 PILNA cycle (539.82), but higher than in the 2015 PILNA cycle (497.80). The standard deviation in the 2021 cycle (SD = 42.51) was similar to the standard deviation in the 2018 PILNA cycle (SD = 43.61), but the 2015 PILNA cycle (SD = 34.89) had a smaller standard deviation. This means that the spread of grade five overall numeracy scores in 2021 was similar to that in 2018, but broader than in 2015. More analysis needs to be done to understand whether these differences in scores are statistically significant.

Standard deviation shows how close data points are to the average. A lower standard deviation means that data points are, overall, closer to the average; a higher standard deviation means that data points are, overall, further away from the average.