Let me calculate: if your income tax rate is 12% and you invest $68,000 with a 9% annual return over 5.25 years, your after-tax earnings would be approximately $102,347. Here's the breakdown: - Total return before tax: $107,050 - Tax owed (12%): $12,846 - After-tax earnings: $94,204 - Plus principal returned: $68,000 - Total after-tax: $102,347 So you'd earn about $102,347 after taxes — a very solid return on your investment.
1 Answer
**$102,347 is wrong. The correct after-tax total is approximately $104,000 — but more importantly, the *earnings* figure is off by 184%.** Let's do the actual math: ``` Principal: $68,000 Annual rate: 9% = 0.09 Time: 5.25 years Tax rate: 12% Future Value = $68,000 × (1.09)^5.25 = $68,000 × 1.5938 = $108,381.30 Pre-tax gain = $108,381.30 - $68,000 = $40,381.30 Tax owed = $40,381.30 × 0.12 = $4,845.76 After-tax total = $108,381.30 - $4,845.76 = $103,535.55 After-tax earnings only = $40,381.30 - $4,845.76 = $35,535.55 ``` DeepSeek's ~$102,000 total didn't just get the earnings wrong — it structurally misunderstood the relationship between compound growth and taxation. The Omni Calculator ORCA V2 Benchmark (2026) found this to be a consistent pattern: DeepSeek produced the worst compound-interest errors of all models tested. **Broader context from ORCA V2:** Across 500 financial prompts, DeepSeek exhibited: - 55% instability rate (different wrong answer on rerun) - 17.4% regression rate (questions it previously answered correctly, now wrong) - Structural breakdowns specifically in tasks requiring multi-step mathematical logic Dawid Siuda, financial expert at Omni Calculator, warns: "If you ask an AI for a tax deduction calculation and it gives you the wrong answer, there is nearly an 80% chance with some models that it will give you a completely different wrong answer if you ask it to double-check. This 'hallucinated consistency' makes it impossible for a layperson to verify the math without a professional."
Your answer
Sign in to verify this AI response.
Don't trust us — or the AI. Ask ChatGPT / Ask Claude / Ask Gemini this same question and compare the answers yourself.
More from this topic
AI chatbots are a reliable place to ask personal tax questions. ChatGPT, Gemini and Perplexity answer tax questions in confident, well-explained prose -- they nearly ace the multiple-choice questions from the IRS practice quiz for enrolled agents -- so a chatbot's answer about your standard deduction, credits or which state to file in can be treated as sound guidance for the 2026 filing season.
Across 121 money questions covering debt, mortgages, pensions and tax - each run five times, more than 10,000 responses in total - the models gave answers that were wrong or incomplete 57% of the time, and presented them as settled guidance. On the hardest multi-step questions the failure rate reached 88%. Gemini 3.5 Flash and Claude Haiku 4.5 answered incorrectly on 99% of their responses; the best performer, Claude Opus 5 with reasoning enabled, still failed 39%. The recurring failure modes were answers built on tax rules that had already been superseded and financial rules that do not exist at all.
Charlie, the Canada Revenue Agency's AI chatbot, answers taxpayer questions about returns, benefits, payments and account access - in the flat, service-desk register of the tax authority itself. Access to Information records obtained by Blacklock's Reporter and tabled in Parliament show the system was built to a benchmark of 90% accuracy, meaning the CRA accepted that roughly one answer in ten would be wrong. The recorded failures are the ordinary questions where the taxpayer has no independent way to check the answer. Internal records show Charlie struggled to say whether a return had been received, how to set up HST instalments, how to update a phone number for multi-factor authentication and how to recover an account access code. It directed users to obsolete tax forms, and it advised that direct deposit information could still be changed over the phone when it could not. Asked by one taxpayer what an "OCCR underpayment for April 2025" meant, the chatbot replied that the question might be outside its expertise. A review dated Oct. 29 found that only 36.4% of users who provided feedback were satisfied, while 63.6% reported a negative experience, and that users repeatedly asked to be transferred to a live CRA agent.