Where's the endless loop?

[Mark17]

I'll have to study both of your responses closely and better understand exactly how they work.

I guess part of me has been thinking the plots accumulate points until they are to be shown at which time all collected points are included. I tried this:

fig=plt.figure()
fig, ax = plt.subplots(2,2)

df = pd.read_csv("C:/Users/Mark/Desktop/SPX_2021_copy.csv")

my_dict = dict(df['DTE'].value_counts())

#for num,key in enumerate(my_dict):
for key in my_dict:
    if key < 251:
        ax[0,0].plot(key,my_dict[key])
    elif (key > 250 and key < 501):
        ax[0,1].plot(key,my_dict[key])
    elif (key > 500 and key < 751):
        ax[1,0].plot(key,my_dict[key])
    elif key > 750:
        ax[1,1].plot(key,my_dict[key])

This output the axes with correct label ranges, but blank graphs themselves with no data plotted.