For those who continue to claim that the GMAT Focus scoring is too easy / the percentiles are inflated, please consider this ESR I found yesterday.
The test-taker answered
just 2 of 21 questions incorrectly on Quant (90.5% accuracy), but only earned an 80/90 Quant section score (66%).
In my opinion, losing 5 section points per question incorrect is indeed a very harsh curve—regardless of the difficulty of those 2 questions. Consider that for every 5 points lost in any section, your GMF total score will drop by exactly 33 and 1/3 points, rounded to the nearest multiple of 5 that ends in a 5.
In addition, there are only 30 available points per section! This means they lost 33.3% of the available section points, despite answering only (2/21) = 9.5% of the questions incorrectly.
UPDATE: another GMF test-taker has reported scoring only 74/90 on Quant (29%), despite answering just 4 of 21 correctly (81% accuracy). That's 4 section points lost per incorrect question.
Conversely, another test-taker reported scoring Q81 (71%) with 6/21 incorrect—though 3 of those errors were on the section's final 3 questions.
UPDATE, 12/17: On the other hand, I recently had a private student score
81 on DI with 8 wrong, Q83 with 6 wrong, and V83 with 6 wrong (composite 655).In conclusion: although on average, questions on the GMAT Focus are worth about 1.5 points per question, this depends significantly on the scoring algorithm and difficulty of questions earned.
At the low end of GMAT Focus scores, each error is worth far more (up to 5 points lost per question incorrect), and at at the high end of scores, each error is worth worth less (around 1 point lost per question).