Use the following formula to set personal records for quickest-streak
relative to an existing personal current record.
(ranked_streak + ranked_streak) / ranked_answers > (current_streak + ranked_streak) / current_answers
E.g., given a current record of 8 correct answers in a row in 1 minute and
20 seconds, to beat that record you'd need: 6 answers in 40 seconds, 7 in
1 minute, 9 in 1 minute 40 seconds, 10 in 2 minutes, etc.