Yorkton
Clear Sky Chart
History

This sumarizes the distribution of each different forecast outcome for the Yorkton clear sky chart from 2005-11-05 to 2017-12-02.

This page is a summary of past forecasts. Even though it's based only on forecasts, some people use these pages as clue to a site's climate. But climate data based on actual observation should be preferred (if you can find it!).

Cloud, Transparency and Seeing forecasts are summarized individually. But because good observing conditions require a combination of minimum cloud cover, transparency and seeing, the individual forecast summaries can be difficult to interpret. The observing conditions section counts the combinations of conditions needed for common types of astronomical observation.

Observing Conditions

The following tables count the occurrence of the combinations of forecast and darkness conditions needed for different observations. Conditions are rated by by what percentage of the hours the observation would likely be attempted are usable.
Observation TypeMinimum conditions for hour to be usableOut of hours
Clear of CloudsTransparencySeeingSky Brightness
Planetary:50%(no limit)Average(no limit)Nighttime Hours
Deep Sky:70%Average(no limit)5.9Nighttime Hours
CCD Imaging:70%Below AveragePoor(no limit)Nighttime Hours

Percentages are of nighttime hours per month, or per year, when a particular observing conditions was met. Deep Sky percentages never exceed 50% because the moon is up half the time. Deep sky percentages are much lower for charts at high latitudes because of fewer dark hours in the summer.

Overall

PlanetaryData
Pts
Deep Sky
Max 60%
Data
Pts
Both Planetary and Deep Sky
Max 60%
Data
Pts
Either Planetary or Deep SkyData
Pts
CCD ImagingData
Pts
Night
38%
16343
12%
47472
7%
16305
42%
16305
21%
33148

By Month

MonthDays of MonthPlanetaryData
Pts
Deep Sky
Max 60%
Data
Pts
Both Planetary and Deep Sky
Max 60%
Data
Pts
Either Planetary or Deep SkyData
Pts
CCD ImagingData
Pts
January1st to 15thNight
29%
895
10%
2622
6%
895
32%
895
15%
1979
January16th to endNight
22%
960
11%
2688
4%
960
28%
960
14%
2090
February1st to 15thNight
36%
870
12%
2459
5%
870
42%
870
18%
1799
February16th to endNight
39%
632
16%
1929
11%
632
44%
632
20%
1364
March1st to 15thNight
37%
720
13%
2160
9%
720
41%
720
20%
1529
March16th to endNight
41%
607
16%
2020
14%
607
48%
607
19%
1373
April1st to 15thNight
41%
539
16%
1781
14%
539
47%
539
26%
1099
April16th to endNight
37%
540
13%
1575
8%
540
41%
540
20%
1119
May1st to 15thNight
37%
540
12%
1440
5%
540
41%
540
26%
977
May16th to endNight
40%
563
8%
1330
4%
561
43%
561
27%
961
June1st to 15thNight
40%
493
2%
1213
1%
493
41%
493
28%
864
June16th to endNight
49%
360
0%
1080
0%
360
49%
360
27%
698
July1st to 15thNight
57%
408
3%
1088
2%
408
59%
408
40%
651
July16th to endNight
64%
564
9%
1387
6%
531
66%
531
49%
762
August1st to 15thNight
64%
539
14%
1432
8%
536
66%
536
40%
849
August16th to endNight
57%
573
23%
1719
18%
573
63%
573
40%
939
September1st to 15thNight
52%
540
16%
1800
15%
540
58%
540
29%
1054
September16th to endNight
47%
537
22%
1974
19%
537
56%
537
29%
1103
October1st to 15thNight
37%
708
17%
2148
11%
708
43%
708
22%
1463
October16th to endNight
36%
960
15%
2496
7%
960
40%
960
24%
1761
November1st to 15thNight
27%
950
12%
2597
6%
950
31%
950
16%
1942
November16th to endNight
25%
975
10%
2925
4%
975
31%
975
14%
2205
December1st to 15thNight
27%
910
6%
2729
4%
910
30%
910
10%
2250
December16th to endNight
27%
960
10%
2880
5%
960
32%
960
11%
2317

Individual Forecasts

The length of each colored bar in the "occurrence of each Forecast" column is proportional to the number of times the chart forecast that color. The percentages are of the total number of hours per month, or per year, with a particular forecast. The colors as the same as those used in clear sky charts.

Note: Transparency probabilities are only counted for those hours that have 30% or less cloud cover. Seeing probabilities are only counted for those hours that have 80% or less cloud cover. If that's too tricky, try Observing Conditions instead.

Overall

Occurrence of each ForecastData
Points
Cloud CoverDay
13%9%47%6%35%45%7%32%
48998
Night
11%9%48%6%35%5%5%7%33%
47623
Cloud CoverDay
13%9%47%6%35%45%7%33%
49008
Night
11%9%47%6%35%5%5%7%33%
47626
Cloud CoverDay
13%9%47%6%35%5%5%7%33%
49008
Night
11%9%47%6%35%5%5%6%33%
47628
Cloud CoverDay
13%8%47%6%35%5%5%7%33%
49006
Night
11%9%47%6%35%5%5%7%33%
47628
TransparencyDay
49%415%22%6%
48666
Night
49%414%22%7%
47472
SeeingDay
17%6%26%28%16%4
6529
Night
15%6%27%33%14%2
16353

By Month

Percentage Cloud Cover NE (2006-)
Color Meanings:
Overcast 90% covered 80% covered 70% covered 60% covered 50% covered 40% covered 30% covered 20% covered 10% covered Clear
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 15thDay
10%12%7%8%9%5%7%6%6%7%19%
1313
16th to endDay
10%11%5%11%9%37%7%5%6%20%
1536
February1st to 15thDay
9%10%410%8%5%7%6%7%7%22%
1414
16th to endDay
8%12%7%9%9%5%7%6%6%6%19%
1544
March1st to 15thDay
12%14%6%8%7%5%6%46%6%22%
1790
16th to endDay
13%13%6%8%6%4445%8%23%
2203
April1st to 15thDay
10%9%48%6%3445%7%33%
2166
16th to endDay
14%9%36%6%25%45%7%34%
2385
May1st to 15thDay
14%9%46%5%35%45%6%34%
2511
16th to endDay
20%7%25%43445%7%32%
2784
June1st to 15thDay
20%6%36%425%5%5%7%31%
2743
16th to endDay
17%7%35%5%35%5%6%7%32%
2880
July1st to 15thDay
10%4245%35%5%6%9%42%
2805
16th to endDay
9%5%245%245%6%8%44%
2684
August1st to 15thDay
9%425%5%35%5%7%8%40%
2520
16th to endDay
14%414423447%48%
2482
September1st to 15thDay
11%6%2442345%6%47%
2160
16th to endDay
13%6%26%423346%45%
1986
October1st to 15thDay
16%12%36%5%24336%34%
1799
16th to endDay
13%12%5%7%5%3445%5%32%
1728
November1st to 15thDay
17%13%6%9%6%24435%26%
1588
16th to endDay
12%13%7%9%9%35%5%46%23%
1365
December1st to 15thDay
11%13%6%13%9%5%7%6%6%415%
1268
16th to endDay
10%14%7%13%8%46%45%6%17%
1344
January1st to 15thNight
8%13%7%10%6%36%5%6%7%23%
2622
16th to endNight
8%11%6%11%8%46%5%6%7%22%
2688
February1st to 15thNight
9%11%37%7%47%6%5%6%27%
2455
16th to endNight
6%10%6%11%6%45%5%6%6%30%
1929
March1st to 15thNight
10%10%5%8%5%35%45%8%31%
2147
16th to endNight
10%11%47%7%4446%8%31%
2020
April1st to 15thNight
8%8%46%5%35%447%41%
1781
16th to endNight
18%8%36%4445%5%5%32%
1575
May1st to 15thNight
17%8%25%5%2345%7%37%
1440
16th to endNight
18%5%25%4345%5%8%34%
1329
June1st to 15thNight
17%6%24445%5%47%37%
1213
16th to endNight
14%5%25%435%45%9%41%
1080
July1st to 15thNight
9%31332336%10%50%
1154
16th to endNight
5%22332335%8%59%
1482
August1st to 15thNight
8%3144245%47%53%
1440
16th to endNight
9%41322345%8%54%
1719
September1st to 15thNight
9%6%245%245%5%7%45%
1800
16th to endNight
13%5%24314447%48%
1974
October1st to 15thNight
16%9%35%5%24445%38%
2148
16th to endNight
12%10%45%5%245%5%6%35%
2496
November1st to 15thNight
13%13%5%8%6%345%46%28%
2597
16th to endNight
9%13%5%10%8%35%447%25%
2925
December1st to 15thNight
9%14%8%13%10%5%5%6%5%5%15%
2729
16th to endNight
8%12%7%15%9%5%6%5%46%18%
2880

Percentage Cloud Cover NW (2006-)
Color Meanings:
Overcast 90% covered 80% covered 70% covered 60% covered 50% covered 40% covered 30% covered 20% covered 10% covered Clear
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 15thDay
10%12%7%8%9%48%5%6%7%18%
1314
16th to endDay
10%11%5%10%9%37%7%5%6%21%
1536
February1st to 15thDay
9%10%410%8%5%7%7%6%8%22%
1414
16th to endDay
8%12%7%9%9%5%7%6%6%5%19%
1544
March1st to 15thDay
11%14%6%8%7%46%46%6%22%
1800
16th to endDay
13%13%6%8%6%4445%7%24%
2202
April1st to 15thDay
10%9%48%7%345%5%7%33%
2166
16th to endDay
15%9%36%6%3445%7%34%
2385
May1st to 15thDay
15%8%36%6%35%446%34%
2511
16th to endDay
20%7%25%5%34448%33%
2784
June1st to 15thDay
20%7%25%5%25%5%5%7%32%
2743
16th to endDay
17%7%35%5%35%46%7%33%
2880
July1st to 15thDay
10%4145%35%5%6%8%42%
2805
16th to endDay
9%5%245%345%6%8%44%
2684
August1st to 15thDay
9%5%25%5%35%5%7%8%40%
2520
16th to endDay
14%423424446%48%
2482
September1st to 15thDay
11%6%2443345%6%47%
2160
16th to endDay
14%6%26%423345%45%
1986
October1st to 15thDay
17%12%36%5%24336%34%
1799
16th to endDay
13%13%5%6%5%3445%5%32%
1728
November1st to 15thDay
17%12%6%9%6%24336%26%
1588
16th to endDay
11%13%6%9%9%35%5%46%23%
1365
December1st to 15thDay
11%13%6%13%9%5%7%6%5%5%15%
1268
16th to endDay
10%15%7%12%8%46%5%5%6%17%
1344
January1st to 15thNight
8%13%7%10%6%36%5%6%7%23%
2622
16th to endNight
8%11%7%11%8%46%5%6%7%22%
2688
February1st to 15thNight
9%11%47%8%47%6%5%6%27%
2448
16th to endNight
7%10%6%11%6%45%5%6%6%30%
1929
March1st to 15thNight
11%10%6%8%5%35%45%7%31%
2160
16th to endNight
10%11%47%6%35%45%7%32%
2017
April1st to 15thNight
8%8%46%435%45%6%41%
1781
16th to endNight
18%8%36%5%345%5%5%33%
1575
May1st to 15thNight
17%8%25%42446%7%37%
1439
16th to endNight
19%5%25%4346%5%7%35%
1330
June1st to 15thNight
18%6%245%445%47%37%
1213
16th to endNight
14%5%15%435%45%9%40%
1080
July1st to 15thNight
9%31332337%10%50%
1154
16th to endNight
5%21332335%8%60%
1482
August1st to 15thNight
8%41442445%7%52%
1440
16th to endNight
10%31321335%8%55%
1719
September1st to 15thNight
9%6%24425%5%5%7%46%
1800
16th to endNight
13%5%2431345%6%48%
1974
October1st to 15thNight
16%9%35%424345%38%
2148
16th to endNight
12%11%46%5%245%5%6%35%
2496
November1st to 15thNight
13%13%5%8%6%34446%28%
2597
16th to endNight
9%13%5%10%9%34447%25%
2925
December1st to 15thNight
9%14%8%13%9%5%5%6%5%5%15%
2729
16th to endNight
8%12%7%14%9%5%6%5%45%19%
2880

Percentage Cloud Cover SW (2006-)
Color Meanings:
Overcast 90% covered 80% covered 70% covered 60% covered 50% covered 40% covered 30% covered 20% covered 10% covered Clear
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 15thDay
10%13%7%7%8%5%7%5%7%7%18%
1313
16th to endDay
11%11%6%10%9%47%7%5%6%20%
1536
February1st to 15thDay
9%10%410%8%5%7%6%6%8%22%
1414
16th to endDay
8%12%7%9%8%5%7%5%7%6%19%
1544
March1st to 15thDay
11%14%6%9%7%45%45%6%22%
1800
16th to endDay
13%13%5%8%6%45%447%25%
2203
April1st to 15thDay
11%8%48%6%35%46%7%33%
2166
16th to endDay
14%9%26%5%345%47%35%
2385
May1st to 15thDay
15%8%37%5%34446%34%
2511
16th to endDay
20%7%35%5%245%5%7%33%
2784
June1st to 15thDay
20%6%35%5%35%45%7%31%
2743
16th to endDay
17%7%25%5%35%46%8%32%
2880
July1st to 15thDay
11%4246%345%7%7%43%
2805
16th to endDay
10%5%145%345%6%8%45%
2684
August1st to 15thDay
9%5%345%35%5%6%8%40%
2520
16th to endDay
14%323423446%49%
2482
September1st to 15thDay
11%6%2443335%7%47%
2160
16th to endDay
14%6%25%433345%45%
1986
October1st to 15thDay
16%11%46%5%24337%34%
1799
16th to endDay
13%13%5%7%5%33446%32%
1728
November1st to 15thDay
17%13%6%9%5%24435%26%
1588
16th to endDay
11%14%6%8%9%35%6%46%23%
1365
December1st to 15thDay
11%13%6%13%9%5%6%7%5%415%
1268
16th to endDay
10%14%7%12%7%46%5%5%6%17%
1344
January1st to 15thNight
8%13%6%10%6%35%5%7%7%23%
2622
16th to endNight
8%11%7%11%8%46%5%6%7%22%
2688
February1st to 15thNight
10%10%47%7%47%6%5%6%27%
2448
16th to endNight
7%10%6%10%7%35%5%6%6%30%
1929
March1st to 15thNight
10%11%6%8%435%45%7%32%
2160
16th to endNight
10%11%46%6%4445%8%32%
2020
April1st to 15thNight
8%8%46%5%35%45%7%41%
1781
16th to endNight
18%8%37%5%25%5%45%33%
1575
May1st to 15thNight
17%7%35%42336%6%38%
1439
16th to endNight
18%6%245%35%46%7%35%
1329
June1st to 15thNight
19%5%245%4445%7%37%
1213
16th to endNight
14%5%15%325%45%8%41%
1080
July1st to 15thNight
9%22432436%10%50%
1154
16th to endNight
5%213323348%60%
1482
August1st to 15thNight
9%2144245%47%53%
1440
16th to endNight
10%313223448%54%
1719
September1st to 15thNight
10%6%244245%5%7%46%
1800
16th to endNight
14%5%23313446%48%
1974
October1st to 15thNight
17%10%35%424345%38%
2148
16th to endNight
13%10%46%5%3445%6%35%
2496
November1st to 15thNight
13%13%6%8%6%335%46%28%
2597
16th to endNight
9%13%5%10%8%35%447%25%
2925
December1st to 15thNight
9%14%7%13%9%5%5%7%45%15%
2729
16th to endNight
8%12%7%14%10%5%5%5%5%5%19%
2880

Percentage Cloud Cover SE (2006-)
Color Meanings:
Overcast 90% covered 80% covered 70% covered 60% covered 50% covered 40% covered 30% covered 20% covered 10% covered Clear
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 15thDay
10%14%6%7%8%5%7%5%7%8%18%
1313
16th to endDay
10%12%7%9%8%47%7%5%6%20%
1536
February1st to 15thDay
8%10%310%8%5%7%6%7%7%22%
1414
16th to endDay
8%13%6%10%8%5%7%6%6%7%19%
1544
March1st to 15thDay
11%13%6%9%7%45%5%5%6%23%
1800
16th to endDay
13%12%5%8%7%45%447%25%
2201
April1st to 15thDay
11%8%47%6%345%6%7%33%
2166
16th to endDay
14%9%35%5%3445%7%34%
2385
May1st to 15thDay
15%8%47%5%25%45%6%33%
2511
16th to endDay
20%6%25%5%245%5%7%33%
2784
June1st to 15thDay
21%6%25%5%35%5%5%8%30%
2743
16th to endDay
18%6%35%5%35%5%6%8%32%
2880
July1st to 15thDay
11%4145%345%6%7%43%
2805
16th to endDay
10%4245%35%5%6%8%44%
2684
August1st to 15thDay
9%5%245%35%6%7%8%41%
2520
16th to endDay
15%423323447%48%
2482
September1st to 15thDay
12%5%25%5%23447%46%
2160
16th to endDay
13%6%25%434345%45%
1986
October1st to 15thDay
16%11%47%424336%34%
1799
16th to endDay
13%13%5%6%5%35%346%31%
1728
November1st to 15thDay
17%13%6%10%5%15%345%26%
1588
16th to endDay
12%13%6%8%10%35%6%46%22%
1365
December1st to 15thDay
10%14%6%13%9%5%7%6%5%5%14%
1268
16th to endDay
10%14%8%12%7%46%5%5%6%17%
1344
January1st to 15thNight
9%13%7%11%6%46%5%5%8%22%
2622
16th to endNight
8%12%7%10%8%46%6%5%7%21%
2688
February1st to 15thNight
9%10%47%7%5%7%6%5%7%27%
2448
16th to endNight
7%10%7%9%7%45%5%5%6%30%
1929
March1st to 15thNight
10%10%6%8%6%25%45%6%32%
2160
16th to endNight
10%11%46%6%4446%8%32%
2020
April1st to 15thNight
8%8%46%6%2445%7%41%
1781
16th to endNight
17%9%26%5%345%45%33%
1575
May1st to 15thNight
18%7%3442445%6%38%
1439
16th to endNight
18%6%25%5%25%5%5%7%35%
1329
June1st to 15thNight
19%6%25%434447%36%
1213
16th to endNight
14%6%25%325%5%5%7%41%
1080
July1st to 15thNight
9%2143245%6%8%51%
1154
16th to endNight
5%213323448%59%
1482
August1st to 15thNight
9%213335%349%52%
1440
16th to endNight
10%413223448%54%
1719
September1st to 15thNight
10%5%244335%5%7%46%
1800
16th to endNight
14%5%2432345%6%48%
1974
October1st to 15thNight
16%11%35%434345%37%
2148
16th to endNight
13%10%46%5%2445%6%35%
2496
November1st to 15thNight
14%14%6%8%6%34445%28%
2597
16th to endNight
10%13%5%10%8%35%45%6%25%
2925
December1st to 15thNight
9%15%7%12%9%5%6%7%5%5%15%
2729
16th to endNight
8%12%7%14%10%46%5%45%19%
2880

Transparency (when cloud cover <= 30%)
Color Meanings:
Too cloudy to forecast Poor Below Average Average Above average Transparent
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 15thDay
61%5%9%19%4
1314
16th to endDay
60%6%11%16%5%
1536
February1st to 15thDay
56%5%18%15%4
1414
16th to endDay
60%310%17%7%
1544
March1st to 15thDay
60%6%13%16%3
1800
16th to endDay
59%413%17%5%
2203
April1st to 15thDay
48%416%21%7%
2166
16th to endDay
48%415%19%10%1
2385
May1st to 15thDay
49%311%25%9%1
2511
16th to endDay
49%5%11%19%13%
2788
June1st to 15thDay
50%413%23%7%
2743
16th to endDay
47%5%18%22%5%
2880
July1st to 15thDay
35%6%20%31%5%
2642
16th to endDay
35%5%21%29%6%
2516
August1st to 15thDay
38%6%22%26%6%
2504
16th to endDay
35%417%35%7%
2482
September1st to 15thDay
36%318%29%9%
2160
16th to endDay
41%314%29%10%
1986
October1st to 15thDay
51%313%24%6%
1799
16th to endDay
52%415%22%4
1728
November1st to 15thDay
59%411%16%7%
1588
16th to endDay
60%5%16%13%3
1365
December1st to 15thDay
69%5%11%11%2
1268
16th to endDay
67%313%13%2
1344
January1st to 15thNight
57%414%17%5%
2622
16th to endNight
59%5%13%14%6%
2688
February1st to 15thNight
53%415%19%7%
2459
16th to endNight
52%312%23%8%
1929
March1st to 15thNight
51%316%23%4
2160
16th to endNight
49%414%23%6%
2020
April1st to 15thNight
42%212%27%13%1
1781
16th to endNight
51%412%18%11%2
1575
May1st to 15thNight
45%39%25%13%1
1440
16th to endNight
47%412%21%12%1
1330
June1st to 15thNight
46%416%21%10%
1213
16th to endNight
40%5%20%26%6%
1080
July1st to 15thNight
29%5%19%36%8%
1088
16th to endNight
22%423%36%11%1
1387
August1st to 15thNight
29%5%23%33%7%
1432
16th to endNight
28%316%36%14%1
1719
September1st to 15thNight
34%6%15%29%12%1
1800
16th to endNight
35%314%31%13%1
1974
October1st to 15thNight
48%314%27%6%
2148
16th to endNight
47%5%17%23%6%
2496
November1st to 15thNight
57%414%16%6%1
2597
16th to endNight
58%416%15%4
2925
December1st to 15thNight
68%411%13%1
2729
16th to endNight
65%410%14%4
2880

Seeing (when cloud cover <= 80%)
Color Meanings:
Too cloudy to forecast Bad 1/5 Poor 2/5 Average 3/5 Good 4/5 Excellent 5/5
MonthDays in MonthOccurrence of each ForecastData
Points
January1st to 15thDay
8%227%32%26%2
90
16th to endDay
25%428%35%7%
96
February1st to 15thDay
11%336%36%12%
90
16th to endDay
13%428%29%19%3
81
March1st to 15thDay
20%435%30%10%
90
16th to endDay
29%6%25%21%16%
219
April1st to 15thDay
14%11%40%25%7%
285
16th to endDay
18%6%29%24%19%2
450
May1st to 15thDay
18%9%27%30%11%2
468
16th to endDay
18%6%24%28%15%6%
517
June1st to 15thDay
20%8%29%25%12%3
495
16th to endDay
17%6%26%26%16%5%
495
July1st to 15thDay
13%6%16%31%23%8%
475
16th to endDay
9%426%31%20%6%
515
August1st to 15thDay
12%221%30%21%11%
493
16th to endDay
14%422%30%21%6%
475
September1st to 15thDay
19%6%30%26%15%1
315
16th to endDay
20%5%26%33%10%2
141
October1st to 15thDay
31%5%24%22%14%
135
16th to endDay
22%6%32%28%6%2
144
November1st to 15thDay
20%6%31%25%14%2
135
16th to endDay
30%7%28%25%7%1
135
December1st to 15thDay
20%418%34%18%5%
94
16th to endDay
15%243%18%17%2
96
January1st to 15thNight
14%7%31%33%11%1
900
16th to endNight
14%9%37%28%8%1
960
February1st to 15thNight
15%5%28%32%15%2
875
16th to endNight
12%425%36%17%3
632
March1st to 15thNight
14%8%25%34%15%2
720
16th to endNight
14%6%27%33%13%4
607
April1st to 15thNight
12%5%32%35%10%2
539
16th to endNight
23%5%25%32%12%
540
May1st to 15thNight
19%7%26%32%13%
540
16th to endNight
22%6%24%29%14%1
563
June1st to 15thNight
20%327%34%11%2
493
16th to endNight
18%422%33%20%1
360
July1st to 15thNight
11%321%39%22%1
408
16th to endNight
7%221%44%20%3
564
August1st to 15thNight
10%216%41%23%5%
539
16th to endNight
12%221%38%23%2
573
September1st to 15thNight
13%323%36%21%1
540
16th to endNight
16%5%25%36%14%2
537
October1st to 15thNight
20%5%26%31%13%2
708
16th to endNight
18%6%28%34%10%
960
November1st to 15thNight
20%7%30%27%12%1
950
16th to endNight
16%9%35%29%8%1
975
December1st to 15thNight
16%5%27%30%15%4
910
16th to endNight
13%6%27%33%16%3
960
Page generated at 2017-12-03 10:16:45. Version ac04

Copyright 2017 A. Danko


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