Hum aaj ka fair price P0 chahte hain. Pehla principle: ek share utna worth hai jitna present value of all cash jo woh kabhi bhi aapko dega — yaani uske future dividends.
Step 1 — ek saal: Agar aapko dividend D1 milta hai aur aap agale saal P1 mein bech sakte hain, aur aap return r maangte hain:
P0=1+rD1+P1Kyun? Kyunki P0(1+r) wahi hona chahiye jo aapko agale saal milega, warna aap kahin aur invest karte.
Step 2 — recursively substitute karein: Lekin P1=1+rD2+P2. Substitute karne par:
P0=1+rD1+(1+r)2D2+P2
Yeh hamesha ke liye chalate rahein. Final price term (1+r)nPn→0 jab n→∞ (ek finite price bahut bade growth se divide hoti hai). Toh:
Step 3 — maanein ki dividends constant rate g se badhte hain: toh Dt=D1(1+g)t−1.
P0=∑t=1∞(1+r)tD1(1+g)t−1
Yeh ek geometric series hai jiska ratio x=1+r1+g hai. Sum karne par (valid hai jab r>g):
P0=1+rD1⋅1−1+r1+g1=r−gD1
r>g KYU zaroori hai: agar dividends aapke discount rate se hamesha tez badhte rahein, toh sum diverge ho jaata hai (infinite value) — economically ek perpetual company ke liye impossible hai.
Liquidation mein agar assets < debt ho toh equity holder ka payoff kya hoga?
Zero (limited liability losses ko invested amount par floor karti hai).
Agar D0 abhi-abhi pay hua hai, toh D1 kya hoga?
D1=D0(1+g).
Required return r badhne par P0 ka kya hota hai?
P0 girta hai (D1/(r−g) mein bada denominator).
Book equity aur market equity mein farq kya hai?
Book = Assets − Liabilities (accounting); Market = expected future cash flows ki PV.
Recall Feynman: 12-saal ke bachche ko samjhayein
Socho tumhara parivaar ek lemonade stand ka malik hai. Pehle tumhe lemons, cups, aur woh paisa chukana hoga jo tumne ek dost se udhar liya tha. Jo bhi coins bacha rahega woh tumhara hai — yahi "bacha hua" hissa equity ki malik hona matlab hai. Kuch din bahut zyada bachta hai (zabardast!), kuch din kuch nahi (sad). Kyunki tum kabhi nahi jaante kitna milega, lekin yeh bahut zyada ho sakta hai, isliye stand ka malik hona exciting hai lekin risky bhi. Bilkul aise hi ek company ka piece (ek share) kharidhna kaam karta hai.