NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

−1.0

−0.5

0

0.5

1.0

Efficiency

Method of prediction in ungaged basins

Figure C1. The distribution of the at-site Nash-Sutcliffe efficiencies of daily streamflow predictions for 

Nash-Sutcliffe Efficiencies of Daily Streamflow Predictions

each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The Nash-Sutcliffe efficiency is along the vertical axis. Nash-Sutcliffe efficiency 

ranges from one to negative infinity; a value of one indicates a perfect fit, while a value of zero indicates 

that a mean value would have produced the same level of accuracy. (The dark line indicates the median 

of the distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data 

point a distance not more than 1.5 times the interquartile range away from the nearest quartile. Data 

points beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, 

have not been drawn.) Method abbreviations are in table 1.
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

−1.0

−0.5

0

0.5

1.0

Efficiency

Method of prediction in ungaged basins

Figure C2. The distribution of the at-site Nash-Sutcliffe efficiencies of the logarithms of daily streamflow 

Nash-Sutcliffe Efficiencies of the Logarithms of Daily Streamflow Predictions

predictions for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The Nash-Sutcliffe efficiency of the logarithms is along the vertical axis. 

Nash-Sutcliffe efficiency ranges from one to negative infinity; a value of one indicates a perfect fit, while 

a value of zero indicates that a mean value would have produced the same level of accuracy. (The dark 

line indicates the median of the distribution, the box outlines the 25th and 75th percentiles, and the 

whiskers extend to the data point a distance not more than 1.5 times the interquartile range away from 

the nearest quartile. Data points beyond this whisker length are defined as outliers and, to increase the 

visibility of the distribution, have not been drawn.) Method abbreviations are in table 1.
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0

500

1,000

1,500

2,000

Root-mean-square error

Method of prediction in ungaged basins

Figure C3. The distribution of the at-site root-mean-square errors of daily streamflow predictions for 

each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The vertical axis indicates the root-mean-square error in units of streamflow. Lower 

values represent less error, on average. (The dark line indicates the median of the distribution, the box 

outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more 

than 1.5 times the interquartile range away from the nearest quartile. Data points beyond this whisker 

length are defined as outliers and, to increase the visibility of the distribution, have not been drawn.) 

Method abbreviations are in table 1.

Root-Mean-Square Errors of Daily Streamflow Predictions
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0

4

2

6

8

10

Root-mean-square-normalized error

Method of prediction in ungaged basins

Figure C4. The distribution of the at-site root-mean-square-normalized errors of daily streamflow 

predictions for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis indicates the root-mean-square-normalized error. 

Lower values represent less error, on average. (The dark line indicates the median of the distribution, 

the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not 

more than 1.5 times the interquartile range away from the nearest quartile. Data points beyond this 

whisker length are defined as outliers and, to increase the visibility of the distribution, have not been 

drawn.) Method abbreviations are in table 1.

Root-Mean-Square-Normalized Errors of Daily Streamflow Predictions
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0

–100

100

200

Average percent error

Method of prediction in ungaged basins

Figure C5. The distribution of at-site average percent errors of daily streamflow predictions for

each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The vertical axis shows the average percent bias. Unbiased methods display a median 

near zero and minimum variability of at-site bias. (The dark line indicates the median of the distribution, 

the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not 

more than 1.5 times the interquartile range away from the nearest quartile. Data points beyond this 

whisker length are defined as outliers and, to increase the visibility of the distribution, have not been 

drawn.) Method abbreviations are in table 1.

Average Percent Errors of Daily Streamflow Predictions
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0

0.4

0.2

0.6

0.8

1.0

Pearson correlation

Method of prediction in ungaged basins

Figure C6. The distribution of at-site Pearson correlations between simulated and observed daily 

streamflows for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis shows the Pearson correlation, which ranges from 

negative to positive one. A perfect correspondence would exhibit a Pearson correlation of one. (The 

dark line indicates the median of the distribution, the box outlines the 25th and 75th percentiles, and the 

whiskers extend to the data point a distance not more than 1.5 times the interquartile range away from 

the nearest quartile. Data points beyond this whisker length are defined as outliers and, to increase the 

visibility of the distribution, have not been drawn.) Method abbreviations are in table 1.

Pearson Correlations Between Simulated and Observed Daily Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0.3

0.6

0.5

0.4

0.8

0.7

0.9

1.0

Spearman correlation

Method of prediction in ungaged basins

Figure C7. The distribution of at-site Spearman correlations between simulated and observed daily 

streamflows for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis shows the Spearman correlation, which ranges 

fromnegative to positive one. A perfect correspondence between ranked streamflow would exhibit a 

Spearman correlation of one. (The dark line indicates the median of the distribution, the box outlines the 

25th and 75th percentiles, and the whiskers extend to the data point a distance not more than 1.5 times 

the interquartile range away from the nearest quartile. Data points beyond this whisker length are 

defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method 

abbreviations are in table 1.

Spearman Correlations Between Simulated and Observed Daily Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0

0.6

0.4

0.2

0.8

1.0

Efficiency

Method of prediction in ungaged basins

Figure C8. The distribution of the at-site Nash-Sutcliffe efficiencies of the daily storage-yield curve

(SYC) for each method of prediction in ungaged basins (PUB) is considered here. See text for a 

description of the methodology used to predict the SYC. The horizontal axis indicates each PUB 

method. The Nash-Sutcliffe efficiency is along the vertical axis. Nash-Sutcliffe efficiency ranges from 

one to negative infinity; a value of one indicates a perfect fit, while a value of zero indicates that a 

mean value would have produced the same level of accuracy. (The dark line indicates the median of 

the distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data 

point a distance not more than 1.5 times the interquartile range away from the nearest quartile. Data 

points beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method abbreviations are in table 1.

Nash-Sutcliffe Efficiencies of the Daily Storage-Yield Curve
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–1.0

0

–0.5

0.5

1.0

Efficiency

Method of prediction in ungaged basins

Figure C9. The distribution of the at-site Nash-Sutcliffe efficiencies of the logarithms of the daily

storage-yield curve (SYC) for each method of prediction in ungaged basins (PUB) is considered 

here. See text for a description of the methodology used to predict the SYC. The horizontal axis 

indicates each PUB method. The Nash-Sutcliffe efficiency of the logarithms is along the vertical 

axis. Nash-Sutcliffe efficiency ranges from one to negative infinity; a value of one indicates a 

perfect fit, while a value of zero indicates that a mean value would have produced the same level 

of accuracy. (The dark line indicates the median of the distribution, the box outlines the 25th and 

75th percentiles, and the whiskers extend to the data point a distance not more than 1.5 times the 

interquartile range away from the nearest quartile. Data points beyond this whisker length are 

defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method 

abbreviations are in table 1.

Nash-Sutcliffe Efficiencies of the Logarithms of Daily Storage-Yield Curve
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0

150

200

50

100

250

300

Root-mean-squared error

Method of prediction in ungaged basins

Figure C10. The distribution of the at-site root-mean-square errors of the daily storage-yield curve for 

each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The vertical axis indicates the root-mean-square error in units of storage fraction 

(time, storage volume divided by mean streamflow). Lower values represent less error, on average. (The 

dark line indicates the median of the distribution, the box outlines the 25th and 75th percentiles, and the 

whiskers extend to the data point a distance not more than 1.5 times the interquartile range away from 

the nearest quartile. Data points beyond this whisker length are defined as outliers and, to increase the 

visibility of the distribution, have not been drawn.) Method abbreviations are in table 1.

Root-Mean-Squared Errors of the Daily Storage-Yield Curve
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0

6

2

4

8

10

Root-mean-square-normalized error

Method of prediction in ungaged basins

Figure C11. The distribution of the at-site root-mean-square-normalized errors of the daily storage-yield 

curve for each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis 

indicates each PUB method. The vertical axis indicates the root-mean-square-normalized error. Lower 

values represent less error, on average. (The dark line indicates the median of the distribution, the box 

outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more than 

1.5 times the interquartile range away from the nearest quartile. Data points beyond this whisker length 

are defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method 

abbreviations are in table 1.

Root-Mean-Square-Normalized Errors of the Daily Storage-Yield Curve
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

100

0

200

300

Average percent error

Method of prediction in ungaged basins

Figure C12. The distribution of at-site average percent errors of the daily storage-yield curve for each 

method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates each 

PUB method. The vertical axis shows the average percent bias. Unbiased methods display a median 

near zero and minimum variability of at-site bias. (The dark line indicates the median of the distribution, 

the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not 

more than 1.5 times the interquartile range away from the nearest quartile. Data points beyond this 

whisker length are defined as outliers and, to increase the visibility of the distribution, have not been 

drawn.) Method abbreviations are in table 1.

Average Percent Errors of the Daily Storage-Yield Curve
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0.95

0.98

0.96

0.97

0.99

1.00

Pearson correlation

Method of prediction in ungaged basins

Figure C13. The distribution of at-site Pearson correlations between the simulated and observed daily 

storage-yield curves for each method of prediction in ungaged basins (PUB) is considered here. The 

horizontal axis indicates each PUB method. The vertical axis shows the Pearson correlation, which 

ranges from negative to positive one. A perfect correspondence would exhibit a Pearson correlation of 

one. (The dark line indicates the median of the distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more than 1.5 times the interquartile range 

away from the nearest quartile. Data points beyond this whisker length are defined as outliers and, to 

increase the visibility of the distribution, have not been drawn.) Method abbreviations are in table 1.

Pearson Correlations Between the Simulated and Observed Daily Storage-Yield Curves
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0.990

0.996

0.992

0994

0.998

1.000

Spearman correlation

Method of prediction in ungaged basins

Figure C14. The distribution of at-site Spearman correlations between the simulated and observed daily 

storage-yield curves for each method of prediction in ungaged basins (PUB) is considered here. The 

horizontal axis indicates each PUB method. The vertical axis shows the Spearman correlation, which 

ranges from negative to positive one. A perfect correspondence between ranked values would exhibit a 

Spearman correlation of one. (The dark line indicates the median of the distribution, the box outlines the 

25th and 75th percentiles, and the whiskers extend to the data point a distance not more than 1.5 times 

the interquartile range away from the nearest quartile. Data points beyond this whisker length are 

defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method 

abbreviations are in table 1.

Spearman Correlations Between the Simulated and Observed Daily Storage-Yield Curves
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

–50

0

50

100

Percent error

Method of prediction in ungaged basins

Figure C15. The distribution of at-site percent errors in the estimated coefficient of variation of annual 

streamflows for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis shows the percent error. Unbiased methods display a 

median near zero and minimum variability of at-site bias. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated Coefficient of Variation of Annual Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

–50

0

50

100

Percent error

Method of prediction in ungaged basins

Figure C16. The distribution of at-site percent errors in the estimated coefficient of variation of daily 

streamflows for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis shows the percent error. Unbiased methods display 

a median near zero and minimum variability of at-site bias. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated Coefficient of Variation of Daily Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–200

–100

0

100

200

Percent error

Method of prediction in ungaged basins

Figure C17. The distribution of at-site percent errors in the estimated 10th percentile of the distribution 

of 7-day average annual-minimum events for each method of prediction in ungaged basins (PUB) is 

considered here. This event is related to the 10-year, 7-day average annual event. The horizontal axis 

indicates each PUB method. The vertical axis shows the percent error. Unbiased methods display a 

median near zero and minimum variability of at-site bias. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated 10th Percentile of the 7-Day Average Annual-Minimum Events
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–200

–100

0

100

200

Percent error

Method of prediction in ungaged basins

Figure C18. The distribution of at-site percent errors in the estimated 50th percentile of the distribution 

of 7-day average annual-minimum events for each method of prediction in ungaged basins (PUB) is 

considered here. This event is related to the 2-year, 7-day annual-minimum event. The horizontal axis 

indicates each PUB method. The vertical axis shows the percent error. Unbiased methods display a 

median near zero and minimum variability of at-site bias. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated 50th Percentile of the 7-Day Average Annual-Minimum Events
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–200

–100

0

100

200

Percent error

Method of prediction in ungaged basins

Figure C19. The distribution of at-site percent errors in the estimated 90th percentile of the distribution 

of annual-maximum events for each method of prediction in ungaged basins (PUB) is considered here. 

This event is related to the 10-year annual-maximum event. The horizontal axis indicates each PUB 

method. The vertical axis shows the percent error. Unbiased methods display a median near zero and 

minimum variability of at-site bias. (The dark line indicates the median of the distribution, the box outlines 

the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more than 1.5 

times the interquartile range away from the nearest quartile. Data points beyond this whisker length are 

defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method 

abbreviations are in table 1.

Percent Errors in the Estimated 90th Percentile of the Annual-Maximum Events
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–200

–100

0

100

200

Percent error

Method of prediction in ungaged basins

Figure C20. The distribution of at-site percent errors in the estimated 90-percent-exceedance streamflow 

for each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The vertical axis shows the percent error. Unbiased methods display a median near zero 

and minimum variability of at-site bias. (The dark line indicates the median of the distribution, the box 

outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more than 

1.5 times the interquartile range away from the nearest quartile. Data points beyond this whisker length are 

defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated 90-Percent-Exceedance Streamflow
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–200

–100

0

100

200

Percent error

Method of prediction in ungaged basins

Figure C21. The distribution of at-site percent errors in the estimated 75-percent-exceedance streamflow 

for each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The vertical axis shows the percent error. Unbiased methods display a median near 

zero and minimum variability of at-site bias. (The dark line indicates the median of the distribution, the 

box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more 

than 1.5 times the interquartile range away from the nearest quartile. Data points beyond this whisker 

length are defined as outliers and, to increase the visibility of the distribution, have not been drawn.) 

Method abbreviations are in table 1.

Percent Errors in the Estimated 75-Percent-Exceedance Streamflow
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–150

–50

–100

0

100

50

150

Percent error

Method of prediction in ungaged basins

Figure C22. The distribution of at-site percent errors in the estimated 50-percent-exceedance streamflow 

for each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The vertical axis shows the percent error. Unbiased methods display a median near 

zero and minimum variability of at-site bias. (The dark line indicates the median of the distribution, the box 

outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more than 

1.5 times the interquartile range away from the nearest quartile. Data points beyond this whisker length 

are defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method 

abbreviations are in table 1.

Percent Errors in the Estimated 50-Percent-Exceedance Streamflow
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

–50

0

50

100

Percent error

Method of prediction in ungaged basins

Figure C23. The distribution of at-site percent errors in the estimated 25-percent-exceedance streamflow 

for each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The vertical axis shows the percent error. Unbiased methods display a median near 

zero and minimum variability of at-site bias. (The dark line indicates the median of the distribution, the box 

outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more than 

1.5 times the interquartile range away from the nearest quartile. Data points beyond this whisker length 

are defined as outliers and, to increase the visibility of the distribution, have not been drawn.) Method 

abbreviations are in table 1.

Percent Errors in the Estimated 25-Percent-Exceedance Streamflow
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

–50

0

50

100

Percent error

Method of prediction in ungaged basins

Figure C24. The distribution of at-site percent errors in the estimated 10-percent-exceedance streamflow 

for each method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates 

each PUB method. The vertical axis shows the percent error. Unbiased methods display a median near 

zero and minimum variability of at-site bias. (The dark line indicates the median of the distribution, the 

box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more 

than 1.5 times the interquartile range away from the nearest quartile. Data points beyond this whisker 

length are defined as outliers and, to increase the visibility of the distribution, have not been drawn.) 

Method abbreviations are in table 1.

Percent Errors in the 10-Percent-Exceedance Streamflow
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

–50

0

50

100

Percent error

Method of prediction in ungaged basins

Figure C25. The distribution of at-site percent errors in the estimated mean daily streamflow for each 

method of prediction in ungaged basins (PUB) is considered here. The horizontal axis indicates each 

PUB method. The vertical axis shows the percent error. Unbiased methods display a median near zero 

and minimum variability of at-site bias. (The dark line indicates the median of the distribution, the box 

outlines the 25th and 75th percentiles, and the whiskers extend to the data point a distance not more 

than 1.5 times the interquartile range away from the nearest quartile. Data points beyond this whisker 

length are defined as outliers and, to increase the visibility of the distribution, have not been drawn.) 

Method abbreviations are in table 1.

Percent Errors in the Estimated Mean Daily Streamflow
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

–50

0

50

100

Percent error

Method of prediction in ungaged basins

Figure C26. The distribution of at-site percent errors in the estimated coefficient of variation (L-CV) of 

daily streamflow for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis shows the percent error. Unbiased methods display a 

median near zero and minimum variability of at-site bias. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated Coefficient of Variation (L-CV) of Daily Streamflow
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–50

0

50

Percent error

Method of prediction in ungaged basins

Figure C27. The distribution of at-site percent errors in the estimated skewness (L-skew) of daily 

streamflows for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis shows the percent error. Unbiased methods display a 

median near zero and minimum variability of at-site bias. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated Skewness (L-Skew) of Daily Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–50

0

50

Percent error

Method of prediction in ungaged basins

Figure C28. The distribution of at-site percent errors in the estimated kurtosis (L-kurtosis) of daily 

streamflows for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis shows the percent error. Unbiased methods display 

a median near zero and minimum variability of at-site bias. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated Kurtosis (L-kurtosis) of Daily Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

–50

0

50

100

Percent error

Method of prediction in ungaged basins

Figure C29. The distribution of at-site percent errors in the estimated lag-1 autocorrelation of daily 

streamflows for each method of prediction in ungaged basins (PUB) is considered here. The horizontal 

axis indicates each PUB method. The vertical axis shows the percent error. Unbiased methods display 

a median near zero and minimum variability of at-site bias. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated Lag-1 Autocorrelation of Daily Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–100

–50

0

50

100

Percent error

Method of prediction in ungaged basins

Figure C30. The distribution of at-site percent errors in the estimated amplitude of the sinusoidal seasonal 

trend of daily streamflows for each method of prediction in ungaged basins (PUB) is considered here. The 

horizontal axis indicates each PUB method. The vertical axis shows the percent error. Unbiased methods 

display a median near zero and minimum variability of at-site bias. (The dark line indicates the median of 

the distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points 

beyond this whisker length are defined as outliers and, to increase the visibility of the distribution, have 

not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated Amplitude of the Seasonality of Daily Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

–40

–20

0

20

40

Percent error

Method of prediction in ungaged basins

Figure C31. The distribution of at-site percent errors in the estimated phase of the sinusoidal seasonal 

trend of daily streamflows for each method of prediction in ungaged basins (PUB) is considered here. 

The horizontal axis indicates each PUB method. The vertical axis shows the percent error. Unbiased 

methods display a median near zero and minimum variability of at-site bias. (The dark line indicates the 

median of the distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the 

data point a distance not more than 1.5 times the interquartile range away from the nearest quartile. 

Data points beyond this whisker length are defined as outliers and, to increase the visibility of the 

distribution, have not been drawn.) Method abbreviations are in table 1.

Percent Errors in the Estimated Phase of the Seasonality of Daily Streamflows
NN−DAR

NN−QPPQ

NN−SMS1R

NN−SMS1L

NN−SMS12R

NN−SMS12L

NN−SM1

NN−SM12

MC−DAR

MC−QPPQ

MC−SMS1R

MC−SMS1L

MC−SMS12R

MC−SMS12L

MC−SM1

MC−SM12

PRMS

NN−AFINCH

MC−AFINCH

0

0.2

0.4

0.6

0.8

1.0

Root-mean-square-normalized error

Method of prediction in ungaged basins

Figure C32. The distribution of the at-site root-mean-square-normalized errors of estimated Fundamental 

Daily Streamflow Statistics (FDSS) for each method of prediction in ungaged basins (PUB) is considered 

here. The horizontal axis indicates each PUB method. The vertical axis indicates theroot-mean-squarenormalized error. Lower values represent less error, on average. (The dark line indicates the median of the 

distribution, the box outlines the 25th and 75th percentiles, and the whiskers extend to the data point a 

distance not more than 1.5 times the interquartile range away from the nearest quartile. Data points beyond 

this whisker length are defined as outliers and, to increase the visibility of the distribution, have not been 

drawn.) Method abbreviations are in table 1.

Root-Mean-Square-Normalized Errors of Estimated Fundamental Daily Streamflow Statistics