Factbox - Greek banks on liquidity drip-feed while Athens haggles with creditors

ATHENS (Reuters) - Greece's banks have been leaking deposits since political turmoil hit the country in December. As a result, they are dependent on emergency liquidity assistance from the Bank of Greece, while Athens haggles with its creditors over reforms. The European Central Bank is keeping a close watch on the situation, adjusting a cap on how much the banks can borrow from the Greek central bank against certain collateral on a weekly basis as long as they are solvent. The central bank's liquidity tap only remains open if the banks have enough collateral. Here are some key facts on the banks based on information from analysts, bankers and official central bank data: GREECE'S BIG FOUR BANKS - National Bank of Greece , Piraeus Bank , Eurobank and Alpha Bank . They account for about 95 percent of the country's banking industry as the debt crisis led to a wave of consolidation in the sector. MARKET CAPITALISATION - The big four have a combined market value of 8.6 billion euros (£6.15 billion) or 21 percent of the Greek stock market's 41.5 bln euro market capitalisation. Bank shares <.FTATBNK> have lost 50 percent year to date, underperforming the broader equities market. DEPOSITS - The balance of household and corporate deposits in Greece's banking system stood at 140.5 billion euros at end-February 2015, down 12.5 percent from the same month a year ago and at the lowest level since March 2005. Including government accounts, overall deposits amounted to 152.4 billion euros at end-Feb. 2015. Deposit flight amounted to 25.4 billion euros from December to February, forcing banks to tap emergency liquidity assistance from the domestic central bank and direct funding from the ECB. EUROSYSTEM FUNDING - Banks had borrowed 38.67 billion euros from the ECB at end-March, using as collateral AAA-rated EFSF (European Financial Stability Facility) bonds after their recapitalisation by Greece's HFSF (Hellenic Financial Stability Fund) bank rescue fund. Emergency liquidity assistance drawn from the Bank of Greece against collateral reached 68.6 billion euros in March. Banks switched to using emergency liquidity assistance in February after being cut off from the ECB's funding window. Emergency liquidity borrowing is more expensive than ECB funding. The ECB cancelled an eligibility waiver that had allowed the banks to submit below-investment-grade government paper as collateral after the new left-wing government halted the country's bailout programme, a condition for access to direct ECB funding. The emergency liquidity cap currently stands at 75.5 billion euros. The ECB has raised it in increments on a weekly basis, keeping track of outflows and pressure on Athens to reach a deal. It has said it would reinstate the eligibility waiver once a deal is agreed. Total Eurosystem borrowing, which includes borrowing from the ECB and the Bank of Greece, reached 107.2 billion euros or about 58 percent of Greece's gross domestic product in March and bankers expect it will increase further in April. COLLATERAL - Greek banks borrow funds from the ECB and the domestic central bank against collateral, including government bonds, T-bills, bank bonds guaranteed by the government (so-called Pillar-2 securities) and performing loans. Banks had a remaining collateral buffer of about 50 billion euros in February for further emergency liquidity financing from the Bank of Greece. The sum has come down to about 40 billion euros currently. GREEK BONDS - Banks hold 5 billion euros in Greek government bonds, representing just 1.4 percent of their total assets. They also hold 3.5 billion euros of short-term T-bills, which is the ceiling the ECB permits as collateral. COLLATERAL "HAIRCUTS" - There is no uniform discount or "haircut" on the nominal value of assets banks submit as collateral, these vary by asset type. On average, the applied discounts range from an estimated 32 to 35 percent, according to bankers and analysts. LOANS AND BAD DEBT - Greek banks have total loans of 259 billion euros, of which 34.2 percent were non-performing (in arrears for more than three months), the highest ratio in the European Union based on central bank data at the end of last year's third quarter. Although the pace of new bad debt formation has slowed, the ratio is expected to have increased since then, bankers estimate. (Reporting by George Georgiopoulos. Editing by Jane Merriman)