Analyze the results of A/B tests conducted over the past three months.  The data includes the test name, hypothesis, control group performance (conversion rate, click-through rate, etc.), variant group performance (conversion rate, click-through rate, etc.), sample size for each group, statistical significance (p-value), and the duration of each test.  Identify the top three most successful tests based on statistical significance and positive impact on key performance indicators (KPIs).  For each of the top three, provide a concise summary of the hypothesis, results, and key learnings.  Additionally, identify the top three least successful tests (those with statistically insignificant results or negative impact on KPIs) and analyze potential reasons for their failure.  The output should be a structured report, including tables summarizing the test results and a narrative analysis of the successes and failures.  The report should also suggest improvements for future A/B testing based on the analysis.  Finally, quantify the overall impact of the successful tests on key business metrics (e.g., revenue, customer acquisition cost).