Migrant workers sending money home has become the biggest source of foreign income in some poor European countries, the World Bank has said.
Globally, remittances make up about $230bn
In a report on European and Central Asian (ECA) nations, the bank said that remittances sometimes beat foreign investment aid and exports in size.
Officially recorded payments in the region - which includes former Soviet states - were over $19bn (£9.67bn).
The largest amount of remittances, as a share of GDP, were sent to Moldova.
The study, using data from 2004, indicated that money sent there by migrants was equivalent to 27% of GDP - an estimated $705m.
Bosnia and Herzegovina (21%; $1.83bn), Albania (16%; $1.16bn) and Armenia (9%; $336m) were among the larger recipients.
Russia attracted migrants from other parts of the former Soviet Union, while poorer Central Asian workers were drawn to countries such as resource-rich Kazakhstan.
TOP 10 REMITTANCE RECEIVING COUNTRIES
6. Bosnia & Herzegovina
8. El Salvador
By percentage of GDP in 2004
Source: World Bank
The payments are a crucial part of the economy, have served as a "cushion" against the economic and political turbulence those countries have experienced, the Bank said.
"For many of the poorest countries in the region [remittances] are the largest source of external financing," the report added.
Some of the money is sent via official transfer services while others send money with friends.
However not all migrants did send remittances, the report found, especially when stays were short.
About 80% of Bulgarians and 62% of Romanians said they were not sending cash back to their home countries while working abroad.
According to the report Germany and France are the only Western European nations in the top-ten list of countries in the world which were receiving migrants.
Since 2004, the UK has experienced its largest influx of immigrants since World War II, largely from new member nations of the European Union such as Poland.
While the report focussed on the ECA nations, the Bank said that Tonga was the nation which had the largest level of remittance income as a proportion of GDP.
In pure monetary value, the latest World Bank figures show that India was the largest recipient of remittances, with about $22bn being sent home in 2005. China and Mexico were also at the top end of the table.
In that year, total remittances globally topped $230bn - of which developing countries received $167bn, more than twice the level of development aid from all sources.
Do you send money home? How is your money spent? Do you feel that sending money back home holds you back in your new life?
Or have remittances helped you? Do you worry about becoming too dependent on relatives working abroad?
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