READ (Especially pp. 28-30 for actual country rankings): John Helliwell, Richard Layard and Jeffrey Sachs (Eds). 2015. World Happiness Report. New York: Sustainable Development Solutions Network.
How is this relative unhappiness (dare we say "sadness"?) determined, though? In a word, empirically. First, the guiding principle for how data on happiness are captured in this report (see p. 19) is stated as follows:
We find the double usage of happiness – both as an emotional report, and as a type of life evaluation – an asset. Answers about happiness yesterday (questions asking for an emotional report) are quite different in structure from answers about happiness with life (questions asking for a judgment about life). There appears to be little doubt that respondents understand the difference and answer appropriately.26 The answers to the emotional reports are similar in structure to those for other emotions, while the “happy with life” answers, as we have already seen, are just like those for other life evaluations.Second, having said all that, the authors go definitively for this approach to delineating happiness (p. 20):
[The] twin facts – that life evaluations vary much more than do emotions across countries, and that these life evaluation differences are much more fully explained than are emotional differences by life circumstances – provide for us a sufficient reason for using life evaluations as our central measure for making international comparisons. But there is more. To give a central role to life evaluations does not mean we need to either ignore or downplay the important information provided by experiential measures. On the contrary, we see every reason to keep experiential measures of well-being, as well as measures of life purpose, as important elements in our attempts to measure and understand subjective well-being. This is easy to achieve, at least in principle, because our evidence continues to suggest that experienced well-being and a sense of life purpose are important influences on life evaluations, above and beyond the critical role of life circumstances.The sum of this two-part argumentation is that our happiness level is a reflection of how our "life circumstances" frame our sense of satisfaction with our lives; that is, with our own perception of the adequacy of our lives.
What are the "life circumstances" (or predictors) used to construct narratives of happiness in WHR 2015? Eight "life circumstances" (or predictors) are specified, as follows (see p. 17):
1. A country's GDP per capita, based on PPP
2. The availability of social support to the individual in "times of trouble"
3. Health Life Expectancy at birth
4. Freedom to shape or direct one's own life
5. Generosity: Self-report of one's philanthropic act or acts "in the past month"
6. The individual's perception of the "spread" of corruption in the public and/or private sectors
7. Positive affect: Average of previous-day affect measures for "happiness, laughter and enjoyment"
8. Negative affect: Average of "previous-day affect measures for worry, sadness and anger..."
Here's how 44 African countries are positioned in the happiness rank-order among 158 countries surveyed around the world, based on the foregoing metrics:
Country - World Rank
1. Libya - 63
2. Algeria - 68
3. Mauritius - 71
4. Nigeria - 78
5. Zambia - 85
6. Morocco - 92
7. Mozambique - 94
8. Lesotho - 97
9. Swaziland - 101
10. Tunisia - 107
11. South Africa - 113
12. Ghana - 114
13. Zimbabwe - 115
14. Liberia - 116
15. Sudan - 118
16. DRC - 120
17. Ethiopia - 122
18. Sierra Leone - 123
19. Mauritania - 124
20. Kenya - 125
21. Djibouti - 126
22. Botswana - 128
23. Malawi - 131
24. Cameroon - 133
25. Egypt - 135
26. Angola - 137
27. Mali - 138
28. Congo Brazzaville - 139
29. Comoros - 140
30. Uganda - 141
31. Senegal - 142
32. Gabon - 143
33. Niger - 144
34. Tanzania - 146
35. Madagascar - 147
36. Central Africa Republic - 148
37. Chad - 149
38. Guinea - 150
39. Ivory Coast - 151
40. Burkina Faso - 152
41. Rwanda - 154
42. Benin - 155
43. Burundi - 157
44. Togo - 158
This list suggests that African countries occupy none of the top 62 positions, or the top 39.2% of the happiest ranks, among the countries surveyed. Conversely, they occupy 29 (or 72.5%) of the bottom 40 countries -- the 40 least happy (or 'saddest') countries! The best placed country is Libya (surprise!). The worst placed is Togo, at 158th position.
We also find that Nigeria, Africa's economic giant, is ranked a lowly 78. South Africa, the second biggest economy, is 113th. Likewise, Zimbabwe is 115th, DRC 120th, Ethiopia 122nd, Kenya 125th, Egypt 135th and Tanzania 146th,
Mauri Yambo 
KheperaTchsef