London — Graffiti that recently appeared on walls in Tananarive, the capital of Madagascar, read: ''The people are hungry; the leaders' bellies are full.''
A few weeks later, violent food riots broke out. Sudan, Malawi, and a host of other African countries have also experienced riots or strikes over food shortages and rising living costs.
An attempt to raise the price of rice in Liberia unleashed such widespread hostility that it was a simple matter for a handful of underprivileged soldiers to topple the government. Similar economic discontent produced yet another military coup in hapless Ghana at the end of last year.
And in Mauritius - where a democratic system obviates any need for coups - the routing of a tolerably good government was so complete that not a single supporter of the ruling party was elected, an event probably unique in the history of democracy.
It is reasonable to speculate that, if free elections similar to those in Mauritius were held in other African countries, at least 75 percent of the present regimes would be turfed out, neck and crop. The plain truth of the matter is that the first generation of independent African leaders not only promised more than they could deliver, but also delivered less than was possible.
One word sums up the present economic situation facing all but half a dozen countries on the continent: catastrophic.
Unless some remedy is found for this condition before the end of the decade, it may be found that all that was wrong about the late Chou En-lai's ominous warning - ''Africa is ripe for revolution'' - is that it was delivered 20 years too early.
Yet, there is also another, altogether more hopeful, side to this picture:
African leaders have begun to learn from their mistakes; some reforms are already taking place; and the huge expenditure that has gone into infrastructure development and education offer a potential to reverse what the famous French agronomist, Rene Dumont, called a false start in Africa in a prescient book published in the early 1960s.
For example, almost all national budgets of African countries now give top priority to expansion of the agricultural sector instead of their early priority , modern-sector development. Nigeria is the outstanding example of this shift: After independence it invested heavily in building a state steel industry, but it has now shifted its priority to ''Operation Feed the Nation.''
Let's take a closer look at the bad news, and it is bad.
Real productive output in the continent is averaging about 3.5 percent, which is just slightly above the average rise in population.
In effect, this means that most countries are, in fact, getting poorer year by year. Export earnings have continued to decline, reaching an estimated $28 billion in 1981, $1 billion less than the year before; and they are still falling. Overall, imports rose by only 10 percent in 1981, which means an increase of just 1.5 percent in real terms, making it the fourth successive year of almost negligible growth in import value.
The aggregate trade deficit of all African countries has continued to rise. Their current account deficit was projected to increase to $13 billion in 1981, which is $2 billion more than the year before.
Translated into more meaningful terms, this means that most countries have enough foreign exchange reserves to finance only a few days of imports, forcing them to scale down on even essential imports, to rely more heavily on foreign loans, and to plunge more heavily into debt.
By the beginning of this year, the continent's long-term external public debt had reached $38.5 billion, which was $4 billion more than in 1979.
What these trends mean for individual Africans is that their income is actually declining. One World Bank forecast suggests that income per head in the poorest countries will fall by 10 percent over this decade. In terms of 1980 dollar rates, per capita annual income in sub-Saharan Africa could fall from $ 260 to only $235 by 1990. The human suffering is immense:
* Over 40 percent of African children under the age of five undergo a period of malnutrition severe enough to result in actual mental or physical damage.
* Out of every 1,000 babies born, 156 die in infancy - compared with 102 in Asia, 24 in Europe, and 19 in North America.
* Illiteracy actually grew by 56 million between 1960 and 1970. Today, only about 43 percent of children are at school.
* An estimated 16 million children age 12 and under are in the labor force. Twenty-seven out of 1,000 children are forced to work in Africa - compared with 14 in Asia, six in South America, and one in Europe and the United States.
The greatest failure of all, though, has been the decline in the continent's production of food, with population growth now actually exceeding the rate of increased agricultural output. It grew by 2.4 percent in 1980 - from only 1.4 percent in 1979. But the average growth of population was in the region of 3 percent.
In Kenya the population is actually growing by 4 percent yearly. Its government recently acknowledged that the country - though agriculturally one of the richest in the continent - had to accept the inevitability of cereal shortages until the end of the decade.
In Rwanda, the population is likely to increase by 2 million to 7 million by 1990; but its land potential makes it impossible to feed even its present population of 5 million.
The UN World Food Council (WFC) has reported that food production in Africa fell by 7 percent per person in the 1960s, declined by another 15 percent in the 1970s, and seemed set to continue this downward slide in the 1980s. Food consumption is 10 percent per capita less than 10 years ago, despite a doubling of grain imports, which are expected to triple by the mid-1980s. Its gloomy forecast was that:
''Hunger and malnutrition during the 1980s are expected to become far more widespread . . . unless concrete measures are intensified to reverse these trends.''
At the same time, increased food imports means increased spending of precious foreign exchange earnings, so adding to the staggering trade deficits.
The failure to control population growth and the continuing impoverishment of the rural areas have resulted in a historic influx of people into the cities. Thus, more people have to be fed, whereas on the land they could at least survive on a subsistence level of agriculture. It also means more frightful slum conditions, and greater visible unemployment.
In Zambia alone the figure for youth unemployment has topped 2.5 million. In Mauritius 20 percent of the labor force is unemployed - many of them educated youth.
The reasons cited by the WFC for the failure to increase food production are poor management, inadequate physical infrastructure, poor production methods, as well as recurrent drought and deteriorating terms of trade between Africa and the industrial nations.
These, too, are the reasons given by the UN Economic Commission for Africa. Its latest report lists as the ''four devastating and debilitating problems'' facing the continent: chronic food deficits, pernicious drought, the impact of apparently inexorably rising costs of imported energy, and the deteriorating terms of trade balance of payments coupled with mounting debts.
So there are five fundamental reasons for Africa's present catastrophic economic condition: natural causes like drought and hurricane; the relative absence of adequate infrastructure, requiring vast expenditures to remedy it; failures of government policies; and the international terms of trade, worsened by the current world inflation and the severe impact of the greater cost of energy imports which results in the increased cost of imported industrial goods.
Little can be done about the climatic hazards. A great deal is possible through more effective government policies. But even with increased efficiency and productivity Africa will still find itself in the trap of the inequitable system of world trade.
A severe limitation of population is clearly of major importance. But as experience has shown this cannot be achieved rapidly, even when strenuously pursued nor, as things now stand, is there any reason for optimism that the North-South dialogue is likely to lead to any serious reforms, at least in the testing decade that lies ahead.
Therefore the best that Africa can hope for is that its present governments will put into better practice the lessons they have already begun to learn. The chief lesson is that priority must go to the agricultural sector. If they do not heed these lessons, they risk being replaced by governments willing and able to stimulate production and ensure a more equitable distribution of what is produced.
What gives reason for hope is that these realities are now thoroughly understood in Africa itself. These have been spelled out with burning clarity in the semantic policy statement - the Lagos Declaration - adopted at the African economic summit two years ago.
Progress on these fronts is seen the drive of many African nations to improve their ability to feed their people. It is also seen in a radical shift in marketing - doing away with big state cooperatives and allowing for freer marketing mechanisms. Tanzania and Mali stand out as countries that have made this shift over the last three years.
Despite all the failures and setbacks, many important developments have in fact taken place over the last 20 years - for example in building roads and railways, improving the level of technical education developing agro-economic industries and other potentially valuable agricultural and irrigation schemes.
A country like Sudan, now at the nadir of its economic fortunes, has already built some of the infrastructure needed and spent huge sums in potentially valuable resource development. These make it possible to climb out of its acute problems fairly quickly given the right political leadership and an improved world economic climate.
While it won't take much to arrest the current state of the continents economic decline, the crucial question is whether the growing political instability caused by the present grim economic conditions will result in plunging Africa into an even worse condition in the coming decade than the parlous state in which it now finds itself.