Ct to Viral Expression Conversion

I have an Excel spreadsheet that contains raw Cycle threshold (Ct) values for both the Citrus yellow vein clearing virus target sequence and my chosen housekeeping gene, Nad5. I need those Ct data converted into meaningful viral expression values so I can compare virus titres across my plant samples.

What I’m after is a clean, well-documented workflow that takes the raw Ct numbers, normalises them against Nad5, and outputs relative expression (e.g., 2^-ΔΔCt or similar) for each sample. Please include an ANOVA so I can see whether titre differences among my treatment groups are statistically significant; if you believe another test would add value, feel free to flag it, but ANOVA results are required.

Deliverables
• A processed spreadsheet (or CSV) with ΔCt, ΔΔCt and final relative expression columns
• A short methods write-up explaining formulas, software, and any assumptions
• ANOVA summary table and a simple plot visualising group differences
• Optional: a small script (R, Python or Excel macro) so I can rerun the analysis on future data
Graphs or tables for scientific publication.

Accuracy and transparency are crucial—I will double-check calculations, so please leave the formulas visible or fully commented. If anything in my raw file needs cleaning or clarification, let me know early so we keep the turnaround quick.