Semakin besar kerugiannya, semakin tinggi taksirannya.

It is a very common Indonesian pattern meaning the more ..., the more ... or the X-er ..., the Y-er ....

So:

• Semakin besar kerugiannya, semakin tinggi taksirannya.
• literally: The bigger the loss, the higher the estimate.

This pattern shows a relationship between two things that increase or change together.

Examples:

• Semakin lama, semakin sulit. = The longer it goes on, the harder it gets.
• Semakin banyak uangnya, semakin boros dia. = The more money he has, the more wasteful he is.

Because each half of the sentence has its own comparison.

Structure:

• Semakin besar kerugiannya = the bigger the loss
• semakin tinggi taksirannya = the higher the estimate

This mirrors English the more ..., the more .... Using semakin only once would not express the full paired comparison as clearly.

In English, the the in the bigger..., the higher... is part of a special comparative structure, not the normal definite article.

Indonesian does not use an article like that here. Instead, it uses the pattern semakin + adjective/adverb.

So:

• English: the bigger the loss
• Indonesian: semakin besar kerugiannya

You should think of semakin as carrying the comparative relationship, not as a direct translation of the.

Kerugiannya comes from:

• rugi = loss / to lose
• kerugian = loss, damage, financial loss
• kerugiannya = the loss / its loss / his-her loss / the loss in question

In this sentence, kerugiannya most naturally means the loss involved or the loss in question.

So it does not necessarily mean someone specifically owns the loss. The -nya here often makes the noun feel more definite or context-linked.

The suffix -nya can do several things in Indonesian. Here, it most likely makes the noun sound definite or contextually known.

So:

• kerugian = loss
• kerugiannya = the loss / the loss involved

and

• taksiran = estimate, appraisal
• taksirannya = the estimate / the appraisal

In other contexts, -nya can also mean:

• his/her/its
• something like the ...
• a general reference to something already known in context

Here, a natural interpretation is:

• the greater the loss, the higher the estimate

Yes, it could, but it would feel a bit less anchored to a specific context.

For example:

• Semakin besar kerugian, semakin tinggi taksiran.

This is understandable, but kerugiannya and taksirannya sound more natural if you are talking about a particular case, report, claim, or valuation.

So the version with -nya feels more like:

• the loss
• the estimate

rather than just:

• loss
• estimate

Taksiran means estimate, appraisal, or assessed value.

It comes from taksir, which relates to estimating or appraising.

Depending on context, taksirannya could refer to:

• an insurance estimate
• a value assessment
• an appraised amount
• a projected figure

So this sentence could be used in contexts like insurance, damage assessment, or valuation.

Because Indonesian often uses tinggi and rendah for numbers, rates, values, prices, estimates, and levels.

So:

• harga tinggi = high price
• angka yang tinggi = a high figure
• taksiran tinggi = a high estimate

Even though English might sometimes say bigger estimate or higher estimate, Indonesian commonly uses tinggi for something that has a value or level.

Because besar is a very common adjective for the size or magnitude of a loss, profit, problem, risk, and similar abstract nouns.

So:

• kerugian besar = a big loss
• keuntungan besar = a big profit
• masalah besar = a big problem

Indonesian chooses adjectives according to natural collocation, just like English does.
You would not usually say kerugian tinggi in normal usage.

Yes. Indonesian often omits a copula like English is/are.

English says:

• The bigger the loss is, the higher the estimate is.

But English usually shortens that to:

• The bigger the loss, the higher the estimate.

Indonesian works similarly, and in fact even more freely. It does not need a verb like adalah here.

So the sentence is complete without any extra verb.

Yes, if you reverse them, the meaning changes only in emphasis, not in the basic relationship.

For example:

• Semakin tinggi taksirannya, semakin besar kerugiannya.

This means:

• The higher the estimate, the bigger the loss.

That is still logically related, but now the sentence starts from the estimate rather than the loss.

So the original order probably reflects what the speaker wants to present as the starting point.

Almost. Makin is a shorter, very common variant of semakin.

So you may also hear:

• Makin besar kerugiannya, makin tinggi taksirannya.

Both are natural.
Very roughly:

• semakin can sound a bit more neutral or formal
• makin can sound a bit more conversational

But in many situations they are interchangeable.

Because semakin already creates the comparative idea.

You usually say:

• semakin besar = bigger and bigger / the bigger
• semakin tinggi = higher and higher / the higher

Using lebih here would usually be unnatural:

• semakin lebih besar ❌

So remember:

• lebih besar = bigger / more big
• semakin besar = increasingly big / the bigger

They are related, but they are not normally stacked together.

It sounds fairly neutral to formal, especially because of the word taksiran, which is common in administrative, financial, legal, or technical contexts.

The grammar itself is completely normal and widely used.
What makes it sound a bit formal is mostly the vocabulary.

A more everyday sentence with the same pattern would be something like:

• Semakin banyak latihan, semakin bagus hasilnya.
• The more practice, the better the result.

A very useful pattern is:

• Semakin + adjective/adverb + noun/clause, semakin + adjective/adverb + noun/clause

Examples:

• Semakin mahal barangnya, semakin sedikit pembelinya.
  The more expensive the item, the fewer the buyers.
• Semakin cepat dia belajar, semakin cepat dia selesai.
  The faster he learns, the faster he finishes.
• Semakin besar risikonya, semakin besar keuntungannya.
  The bigger the risk, the bigger the profit.

So the sentence you were given is a good model for a very productive Indonesian structure.