Vol.26 No.1 |
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|
Year | Volume |
2021 |
28.1
|
28.2
|
2020 |
27.1
|
27.2
27.3 | 27.4 27.5 | 27.6 27.7 | |
2019 | 26.1 | |
2018 | 25.1 | |
2017 |
24.1
|
24.2
24.3 | 24.4 24.5 | 24.6 24.7 | 24.8 24.9 | |
2016 |
23.1
|
23.2
23.3 | 23.4 23.5 | 23.6 23.7 | 23.8 |
2015 |
22.1
|
22.2
22.3 | 22.4 22.5 | |
2014 |
21.1
|
21.2
21.3 | |
2013 |
20.1
|
20.2
20.3 | 20.4 |
2012 |
19.1
|
19.2
19.3 | 19.4 |
2011 |
18.1
|
18.2
|
2010 | 17.4 |