The foreign institutional investors party continues on Dalal Street [Get Quote] unabated, with net investment by FIIs in stock markets surging past the $50-billion milestone for the first time in the country's history.

Despite a brief lull in first half of this year, the grand total of FII investment in equities rose to an all-time high of $50.025 billion on Friday, the latest data available with stock exchanges shows.

Add to this about Rs 5,500 crore (Rs 55 billion) invested by the FIIs in debts and the total FII investment in the country since their entry soars to over $51.13 billion, the Securities and Exchange Board of India data shows.

Foreign funds have been net buyers throughout this year except in May, when the markets had plunged sharply, largely due to a sell-off by overseas investors.

Net FII inflow in equities has risen to $8.92 billion (Rs 408.14 billion) so far this year as against $10.7 billion in entire 2005.

In the last month alone, FIIs were net buyers of shares worth Rs 9,380 crore (Rs 93.8 billion), which is their highest net inflow in a month this year and the second highest monthly investment ever.

FIIs were net sellers in stocks only on three days during the past month. The highest ever one-month net investment by FIIs was made in December 2005 when they made net purchase of shares worth Rs 9,465 crore (Rs 94.65 billion).

The total FII net investment in the country's stock market stood at $41.10 billion at the end of last year.

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