8 september 2014

Setting the coverline in Celsius

Setting your coverline when you are charting in Celsius is no different than setting your coverline than if you were using Fahrenheit. Yet, most how-to's are written for the Fahrenheit audience, presumably the North American audience. While it's great that these how-to's are written at all online (they're scribbled down by people who have read a book about it or learnt from a teacher, who in turn have read about it and educated themselves), it might be convenient to have a how-to for the Celsius audience as well. That's why I'm writing this post! I'm writing this to you and to myself, in case I'd ever need to refresh my memory.

Okay. How does one draw a coverline?
To draw a coverline, you need to have noticed a temperature shift. A temperature shift occurs in your cycle at some point because of the effect the hormones estrogen and progesterone have on it. While estrogen is dominant, your BBT is lower. When progesterone is dominant, your BBT is higher. Have a quick look at this nifty little how-to, as that is what I will be replicating, just that this time, it'll be with the correct numbers for Celsius. I found it to be the clearest in terms of applicating to your own chart.


  1. Identify a temperature that is at least 0.11 degrees higher than that of the previous 6 days'.
  2. Highlight those previous 6 days.
  3. Identify the highest of those 6 temperatures
  4. Draw a straight, horizontal line that is 0.056 degrees higher than that of the highest temperature of the highlighted temperatures.
  5. You're done! Finito!

Note: I did round these numbers a bit, but only appropriately so. A conversion from Fahrenheit numbers gives way too many decimals to be remembered easily, and the rounding is not going to affect accuracy. Do not stress about drawing the line at 0.056 or 0.055 if you are charting on paper, it really won't make a difference because the difference between the numbers is miniscule.