MONTHLY SCORE is a sum of DAILY SCORES of all finished puzzles THIS month.
For example, if it's May now, and you finished three puzzles this month: one is May 2 (8950 pts), the second one is May 5 (9450 pts), and the third is May 7 (8200 pts), your monthly score after May 7 puzzle will look like:
MONTHLY SCORE = (May 2 score) + (May 5 score) + (May 7 score) = (8 950 pts) + (9 450 pts) + (8 200 pts) = 26 600 pts
MONTHLY SCORE = score1 + score2 + ... + scoreN
Please note, that when new month starts, your MONTLY SCORE will start calculation again from 0.
To calculate the DAILY SCORE, we need to find the percent of completed without help, calculate time bonus, and take a daily bonus if it's today's puzzle.
DAILY SCORE = SCORE + TIME BONUS + DAILY BONUS.
SCORE = % of completed without help * 100
% of completed without help is basically percent of filled cells without using "Reveal" and "Check" feature.
TIME BONUS = (300sec - Time Spent to solve puzzle) * 10
Player gets his time bonus only if he finished puzzle faster than in 5 minutes (300sec). So his bonus will be 5 min - time he spent to solve puzzle.
DAILY BONUS = 50
Daily bonus is a constant and player will get it only when he plays today's puzzle.
Let's take a look at the screenshot above, and calculate the score step-by-step.