My initial intuition was "surely there were more non-farmers", but I did some calculations and it looks closer than I thought. 

I had a go at a guesstimate model, where I estimate the number of humans who lived in each period, the % of them having offspring, the chance that I descend from them, and an estimate % who are farmers in each period. 

I get 11 billion non-farming ancestors, and 4.6 billion farming ancestors (around 3.6 billion exclusively/mainly farmers).

What I see as the "crux period" is 0 BC - 1200 AD; I can't find any data how many of the humans in that period are likely to have been my/your ancestors. I've put 15-40%, but if it's closer to 60%, farmers might edge it. Also, I haven't accounted for lineages ending - aside from individuals not having offspring (which I take as a constant in the model), there may have been some huge lineage collapses, presumably more before farming than after.
 

Wikipedia suggests an average of 50,000 individuals for prehistoric humans in Africa. Population sizes after farming were so much larger, that I would expect the majority of my ancestors to be farmers. 

Providing a sensible answer is dependent on arriving at a sensible interpretation of the question.  I'll assume that it is aimed at understanding to what degree farming or non-farming lifestyles have had an influence on the selection of genes that you carry.  I assume that "farming lifestyle" includes people who don't actually farm, but obtain food from farmers, one way or another.

On that basis, and assuming you are a typical inhabitant of a society that hasn't recently engaged in much hunting/gathering (maybe some fishing, but not dominant), I would say that about 1/30 of your ancestors were of a farming lifestyle.  That is, if you trace back what the selective influences were on your ancestors, about 1/30 of it was selection for reproduction in a farming community.  I get the 1/30 by dividing 300,000 years of homo sapiens into 10,000 years of agriculture. 

I don't think the population sizes at different times, and collapse of the pedigree (some of your ancestors being the same people), make any difference.  It might make a difference if the number of children per person varied, since each child is a new object for selection, but I think this may be rather constant until very recent times.  And of course, the number of children who survive to reproduce themselves is close to two at all times. (The population has grown over time, but at nowhere near the rate it would if, say, three children per couple survived to reproduce themselves.)

Now, depending on how quick evolution can act, the fact that the 1/30 of the selection influence is the most recent 1/30 could be crucial.

One thing to consider is that we have more female ancestors than male ones, because males are far more likely to fail to breed, while also having the option to be much more successful breeders.
And historically, men were far more likely to be farmers (in a literal sense, farming plants being their main occupation, lifestyle and a source of calories) than women. 
Or to put it differently: between about 12000 BC, and about 1800 AD, there majority of women were WIVES of farmers, but not farmers themselves (due to division of labor, the vast majority of women did jobs related to the production of cloth and non-farmign products, while men did the farming), while at the same time, there was a big % of men who were farmers (often unfree to some degree) who died childless.
Moreover, farmers usually stayed on the same land for a long time, intermarrying with their neighbors, thus particularly virile farmers eventually became ancestors to a lot of their neighborhood, while unsuccessful, poor, or unfree farmers had few or no children.
Women, moreso than men, would marry-out and leave their ancestral household, thus spreading their genes.
So we might end up with a calculation where you have a lot of Spinner and Weaver ancestors, but fewer Farmer ancestors.

According to this, there were only 9 billion humans alive before the agricultural revolution, as compared to 109 billion who have lived and died:

https://en.wikipedia.org/wiki/Estimates_of_historical_world_population#/media/File:Illustration_of_contemporary_and_past_human_populations_Our_World_in_Data.png

Populations got much bigger post-Industrial revolution, after which very few people were farmers. I'm pretty sure more people who have existed were non-farmers just from that growth, by a huge margin.

But I'm not sure whether or not that should carry over to ancestors. On one hand, you can only have so many ancestors at a time, and explosive industrial population growth doesn't change that. But smaller farming populations might mean more of my family tree crossing over itself, and so fewer unique farming ancestors?

I would expect the general breakdown to be a few recent generations of maybe not farmers, several thousand years of mostly farmers, and then the remainder of the time between the dawn of humanity and the beginning of agriculture being "farmers didn't exist yet".

Exactly when agriculture began isn't an entirely settled question, but there doesn't seem to be any suggestion that it was early enough to make up any more than a small fraction of the last 300k years.

Even if you include some proto farming, like a hunter-gatherer occasionally choosing to scatter seeds in a convenient foraging spot, I don't know if you get back to 150kya (or whenever the halfway point would be when accounting for changing generation times, and counting ancestors rather than years)

Or are we thinking that it gets weirder when you account for population size expanding after farming? That would provide more people to be distinct ancestors (past a certain point, everyone who was alive at the time either has no living descendants or is a universal ancestor), but I'm dubious of that out weighing the long (long) period of pre-farming.

Yamnaya ancestry (Indo-European steppe-pastoralists) make up a large percentage of European genetic ancestry. Modern Europeans are a mixture of three ancestral populations: steppe-pastoralists from the east (Yamnaya...), Western huntergathers, and Anatolian farmers. In some Northern Europeans, the fraction of farmer ancestry may be less a minority. 

"Yamnaya–related ancestry is found in the DNA of modern Central, and Northern Europeans (c. 38.8–50.4 %), and is also found in lower levels in present-day Southern Europeans (c. 18.5–32.6 %), Sardinians (c. 2.4–7.1 %), and Sicilians (c. 5.9–11.6 %).^{[80][71][13]"}

https://en.wikipedia.org/wiki/Yamnaya_culture#:~:text=Yamnaya%E2%80%93related%20ancestry%20is%20found,%25)%2C%20and%20Sicilians%20(c.

Okay, assuming this means "how many Homo Sapiens ancestors did you have that spent substantial amounts of their working life farming", I think every human being alive has around 25x more non-farmers than farmers as ancestors.  I think the ratio is so large that the answers doesn't change even if you ask "how many ancestors lived in agricultural societies" instead of "how many ancestors were farmers" and regardless of where your ancestors were - even comparing people whose ancestors were all in a place that invented agriculture early vs someone whose ancestors didn't start farming until after the industrial revolution.

The only thing that matters, to the extent that it swamps every other variable, is how long humans have been farming.  Per Wikipedia, Agriculture developed in multiple places around the world after the last Ice Age, ~10,000 years ago.  Homo Sapiens is about 30 times older evolving ~300,000 ago.  The number of years your ancestors could have possibly been farmers is a rounding error compared to that.

I don't think changing generation length matters much - it's probably between 15 and 30 years for basically all your ancestors up to the modern day, nowhere near the ratio it would need to make a difference to the answer.  Pedigree collapse (some of your ancestors show up in multiple places in your family tree, moreso the farther back you go) matters, but again it can't possible swamp the ~30x difference in number of generations.  And, at the very least, you're guaranteed to have at least 2 ancestors per generation.

This is a great question, thanks for posting it!

Linch, unless you are African then you have 1% to 4% Neanderthal genes, there was interbreeding and presumably we had "mixed"  individuals on both sides. Neanderthal (and Denisovans etc) must have had similar levels of consciousness to us so there would have been an exchange of culture. Homo Sapiens are not your only ancestors.

If ancestor is parent/mother/grandparent etc but nothing else. Obviously non hunters.

If we count how many people dead or alive are you related to. Farmers.