Most courses meet be in the progressive. She is walking. They were singing. The rule is simple: be and an -ing form make a continuing action, and the -ing form is the main verb.
Now count. Chapter XXVI has 137 forms of be. The lab reads the word after each one, past not and short adverb words, and sorts it. It finds six followed by an -ing word. That is 4.4%.
What the other 131 are
37 are followed by a noun phrase: his arrival was no great, her brother is the cause. 26 are followed by a preposition or a place: I am not in love, she was at length. 19 have an adjective the scan knows: I am not afraid of. 13 have a participle. Three put a pronoun next. One is a question turned round, how am I even to know; the other two are as it is, you must, where the scan ran past a dash, and were I distractedly in love, the old form for a case that is not real, which “The -s Belongs to He, She and It” set aside. Thirty-three are filed as something else.
After a noun phrase, an adjective or a place, be is the verb. Its job is to link the subject to what comes after: her brother is the cause. There is no other verb for it to help. And not one of the 137 is followed by a bare verb. I am agree and she is work here put be in front of a verb with no ending, and the chapter never does: after be comes an -ing form, a participle, or no verb at all.
The participle you cannot sort
The 13 participle forms are a mix. You are warned against it says what is done to you, and she was satisfied with says how she felt. A passive and an adjective use the same word in the same place, and a scan that reads only the word cannot tell them apart. The lab puts them in one class and says so under the table.
The thirty-three the scan lost
Read the rows filed as something else. You will find I am sure and I am certain more than once, where sure and certain are adjective words the scan does not know. You will find tempted, deceived and resented, participle forms it does not know. You will find as before an adjective: was as regular, be as welcome. A few rows are broken: what was Charlotte's first.
One the scan lost
One of those rows is the progressive. In his marriage was now fast approaching the scan steps over now, meets fast, which is on none of its lists, and stops. By hand, then, 7 of the 137 forms of be are followed by an -ing verb, 5.1%, close to the novel's 4.7% and the scan's 4.4%. The page keeps the scan's number and prints the rows, and the rows are where you check it.
Over the whole novel
Counted once over the whole novel, which no page can carry, and quoted here: 5,858 forms of be. A noun phrase follows 23.5%, a participle 20.8%, a noun or name 14.3%, a preposition 12.6%, an adjective 10.4%, an -ing form 4.7%, and a pronoun 2.4%. For the play the -ing share is 5.6%. In the two modern documents the lab counts 2 of 36 forms followed by an -ing word, which is 5.6%, and 5 followed by a participle. The picture is the same in 1813 and in 2026.