Want more evidence that Microsoft’s (MSFT) Windows RT Surface has been a bomb? Consider that Barron’s has rounded up analyst estimates and has found that Microsoft sold 1 million Surface tablets at best last quarter. Want some lower estimates? Barron’s says that Citigroup analyst Walter Pritchard thinks Microsoft sold between 700,000 and 800,000 Surfaces last quarter, while Goldman Sachs analyst Heather Bellini pegs Surface sales at a measly 230,000 units. Of course, the Surface brand could get a boost in the near future if businesses take a liking to the Surface Pro over the next months, but for the time being it looks as though Microsoft’s first effort at selling tablets has been a bust.