Table 2 Mean household beverage expenditure in Tonga before and after a sweetened-beverage tax
Outcome | 2009 (95% CIs) | 2015/16 (95% CIs) | Absolute difference (t-test 95% CIs) | % change (95% CI) | p-value | |
|---|---|---|---|---|---|---|
Purchasing prevalence (% households) | All beverages | 72.3 (69.6 to 74.9) | 80.9 (78.4 to 83.3) | 8.6 (5.0 to 12.2) | 11.9 (6.6 to 17.3) | < 0.001 |
Soft drinks | 51.3 (48.3 to 54.3) | 40.4 (37.3 to 43.5) | −10.9 (− 15.2 to −6.5) | −21.2 (−28.7 to − 13.4) | < 0.001 | |
Milk | 29.9 (27.3 to 32.4) | 44.5 (40.7 to 48.4) | 14.6 (10.0 to 19.3) | 49.0 (31.3 to 67.8) | < 0.001 | |
Bottled water | 10.4 (8.7 to 12.1) | 35.0 (31.5 to 38.4) | 24.6 (20.7 to 28.4) | 236.5 (176.3 to 306.0) | < 0.001 | |
Mean expenditure (2015/16 T$ /person/year) | All beverages | 83.8 (73.6 to 94.0) | 116.0 (100.6 to 131.4) | 32.2 (13.7 to 50.7) | 38.4 (14.4 to 64.5) | 0.001 |
Soft drinks | 37.9 (31.1 to 44.7) | 29.6 (22.5 to 36.8) | −8.2 (−18.1 to 1.6) | −21.8 (−44.1 to 3.2) | 0.102 | |
Milk | 22.7 (19.7 to 25.8) | 35.4 (28.7 to 42.2) | 12.7 (5.2 to 20.1) | 55.7 (20.6 to 93.6) | 0.001 | |
Bottled water | 6.0 (3.4 to 8.6) | 26.6 (20.9 to 32.3) | 20.5 (14.3 to 26.8) | 341.1 (155.7 to 621.0) | < 0.001 | |
All food and beverages | 2500 (2310 to 2680) | 2150 (2020 to 2280) | − 344 (− 573 to − 115) | −13.8 (−21.9 to − 5.2) | 0.003 | |
Beverage expenditure as a proportion of household food budget (%) | All | 3.20 (2.94 to 3.45) | 5.41 (4.61 to 6.21) | 2.22 (1.38 to 3.06) | 69.4 (41.5 to 98.3) | < 0.001 |
Soft drinks | 1.39 (1.24 to 1.55) | 1.32 (1.07 to 1.58) | −0.07 (−0.37 to 0.22) | −5.2 (−25.7 to 16.5) | 0.633 | |
Milk | 0.87 (0.77 to 0.97) | 1.68 (1.44 to 1.93) | 0.82 (0.55 to 1.08) | 94.2 (59.4 to 131.7) | < 0.001 | |
Bottled water | 0.21 (0.14 to 0.28) | 1.31 (0.78 to 1.85) | 1.11 (0.56 to 1.65) | 532.5 (230.7 to 906.0) | < 0.001 | |
Beverage expenditure per person as a proportion of equivalised income (%) | All | 0.87 (0.75 to 1.00) | 1.20 (1.02 to 1.39) | 0.33 (0.11 to 0.56) | 38.3 (10.5 to 69.0) | 0.004 |
Soft drinks | 0.39 (0.33 to 0.45) | 0.32 (0.23 to 0.42) | −0.07 (−0.18 to 0.05) | − 17.0 (−44.5 to 12.8) | 0.267 | |
Milk | 0.23 (0.19 to 0.27) | 0.33 (0.28 to 0.38) | 0.10 (0.04 to 0.17) | 43.2 (12.0 to 79.1) | 0.002 | |
Water | 0.07 (0.00 to 0.13) | 0.23 (0.18 to 0.29) | 0.16 (0.08 to 0.25) | 234.3 (−63.5 to 1072.1) | < 0.001 | |
Estimated quantity of beverages acquired (kg/person/year) | All | 56.1 (46.6 to 65.5) | ||||
Soft drinks | 10.2 (7.9 to 12.4) | |||||
Milk | 10.3 (8.3 to 12.2) | |||||
Bottled water | 27.5 (20.7 to 34.4) |