After battling Palpatine, Yoda went into exile on Dagobah, and Luke became his final apprentice.
He became a Jedi Master at around 100. This gives him 800 years to train 20,000 pupils. 20000/800=25, so by that logic he trains approximately 25 Jedi a year. 25 pupils a year.
The Grand Master's apprentice
At one time, Dooku was the Padawan of Yoda, the Grand Master of the Jedi Order. In 86 BBY, Dooku later completed his Initiate Trials and hoped to be selected as the Padawan apprentice to Lene Kostana due to her mission in hunting down relics associated with the dark side.
Like all in the Order, the young Korun boy was taught by Grand Master Yoda when he was a learner, and eventually went on to become a Padawan to another Jedi. At one point during his apprenticeship, Windu trained under Master T'ra Saa.
Billaba became Windu's Padawan and trained under the Jedi Master in the ways of the Force. During her training, Windu allowed her to study Form VII variant known as Vaapad. She eventually became a Jedi Knight, renowned for her skills with a lightsaber and favored Form III when teaching other Jedi.
Bottom line, Dooku never considered himself a Sith. And he wasn't; he was a man looking to change the galaxy in a way the Jedi were unwilling to try. And that is why he joined the Sith and became Darth Sidious' apprentice, Darth Tyrannus. When Dooku became Sidious's apprentice, he was already an elderly man.
His former colleagues in the Jedi Order saw Dooku as misguided but a man of principles, and refused to believe he could be an advocate of violence and war. They were wrong; Dooku had sworn allegiance to the Sith Lord Darth Sidious, taking the name Darth Tyranus.
Who was Qui-Gon Jinn's Master? Qui-Gon Jinn's Master was Count Dooku. The relationship between Dooku and his Padawan was largely built on respect, though Jinn often found it difficult to get a read on his Master.
He began training under Master Yoda as a youngling until Qui-Gon Jinn chose him as an apprentice when he was 13 years old. By the time Obi-Wan was 17, their clashing personalities made for a rocky relationship -- but their bond evolved into a true partnership after a harrowing mission on Pijal.
16 His Apprentice Turned To The Dark Side
However, if we look at the Star Wars novels, we can find that he actually had three Padawans in total. Qui-Gon Jinn's second Padawan was a boy named Xanatos from the planet Telos IV.
The second time Yoda mentions his long life is in Return of the Jedi, when he tells Luke, “When you reach 900 years old, you will not look as good as you will.” If we take Yoda at his word, that means the Jedi Master died at the ripe old age of 900.
Legend had it that Yoda—a Jedi who became Grand Master—was trained by N'Kata Del Gormo. A Force-sensitive Hysalrian, N'Kata Del Gormo was trained in the ways of the Force and achieved the rank of Master within the Jedi Order.
Neither lightsabers nor the Force could help Yoda defeat Darth Sidious. Though Yoda was able to keep his adversary on his toes, he was unable to end the conflict, and their duel ended with no clear victor.
Yoda kept a second lightsaber on Dagobah inside his hut in 3 ABY after his previous one was lost during a duel in the Galactic Senate and then incinerated during a celebration of the Jedi Order's eradication in 19 BBY. Luke Skywalker eventually had the lightsaber in his possession after Yoda's death in 4 ABY.
Dooku belonged to the aristocracy, and his weapon reflected an older, more chivalric style than the Jedi he faced. It also reflected his status as the head of the Separatists: the lightsaber looked far more ceremonial than practical, suggesting that he himself did not face combat nearly as much as the Jedi did.
A Sith Lord with the ability to prevent death and create life, Plagueis is the mentor of Sheev Palpatine/Darth Sidious, who, in accordance to the Sith's Rule of Two, eventually betrays Plagueis by murdering him in his sleep, taking his place as Sith Master.
In his final bout, Dooku lost his Sith lightsaber to the Jedi Knight Anakin Skywalker once he was defeated in a duel aboard the starship Invisible Hand. Skywalker used Dooku's own weapon to behead the Sith Lord and end his life.
Another contender for the weakest Sith could be Count Dooku, or has he's also known Darth Tyranus. Dooku was a cunning and talented Sith Lord, known for his swift skills with a lightsaber and his ability to manipulate populations.
Qui-Gon Jinn was called a Grey Jedi by his peers for defying the council in training Anakin Skywalker (and then passing his training on to Obi-Wan Kenobi).
In the now-abandoned Legends continuity, his birth name appeared to be Maul, with the title of "Darth" simply added to it when he was taken on as an apprentice by Darth Sidious.
In 19 BBY, the lightsaber was lost when it was dropped out of the window of Supreme Chancellor Palpatine's office prior to his death. In 18 BBY, Duros salvagers recovered it and gave it to Senator Sano Sauro.
Darth Plagueis was a legendary Dark Lord of the Sith trained by the Sith Master Darth Tenebrous.